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PMS 205

NWCG Glossary of Wildland Fire

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NWCG Glossary of Wildland Fire, PMS 205

Overview

The NWCG Glossary of Wildland Fire provides an extensive listing of approved terms and definitions used by the NWCG community. It contains terms commonly used by NWCG in the areas of wildland fire and incident management and is not intended to list all terms used by NWCG groups and member agencies. The NWCG has directed that all committee and subgroup product glossaries be contained within the NWCG Glossary of Wildland Fire to maintain definition consistency and clarity among documents.

Comments, questions, and recommendations shall be submitted to the appropriate agency program manager assigned to the Data Standards and Terminology Board (DSTB). 

NWCG Glossary of Wildland Fire, PMS 205  (Quick View)

EDG Explorer is a database platform used for managing NWCG Glossary terms.  The following table is a quick view of the terms found in EDG. More detailed information such as rules, documentation, and term relationships may be viewed in EDG Explorer.  

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Term Steward Status Definition
ABCD Miscellaneous Data Management Committee DMC, Incident Business Committee IBC Approved A FireCode used by the USDA Forest Service to track and compile cost information for emergency initial attack fire suppression expenditures for A, B, C, & D size class fires on Forest Service lands.
abort National Interagency Aviation Committee NIAC Approved To jettison a load of water or retardant from an aircraft, or terminate a preplanned aircraft maneuver.
abort area National Interagency Aviation Committee NIAC Approved A designated area where unused quantities of water or fire retardant may be jettisoned, usually to permit an airtanker to land with less than a full load.
Above Ground Level National Interagency Aviation Committee NIAC Approved Term frequently used in aviation operations, usually in connection with a stated altitude.
absolute humidity Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, (also called vapor density). In a system of moist air, the ratio of the mass of water vapor present to the volume occupied by the mixture; that is, the density of the water vapor component.
absorption Communication, Education, and Prevention Committee CEPC Approved Act of soaking up and retaining a gas in liquid or in a solid; also retention of radiant energy.
accelerant Communication, Education, and Prevention Committee CEPC Approved Material (usually a flammable liquid) used to initiate or increase the spread of a fire.
acceptable fire risk Fire Use Subcommittee FUSC Approved The potential fire loss a community is willing to accept rather than provide resources to reduce such losses.
accessibility burn Fire Use Subcommittee FUSC Approved The burning of understory prior to the sale of forest products to improve the efficiency of timber marking and harvesting.
accident (event) National Coordination System Committee NCSC Approved An event, usually managed by organizations external to the fire community, for which the primary focus is for dealing with an accident and assistance to potential victims. This category includes accidents such as: automobile, aircraft, train, watercraft, and industrial.
accounting code Incident Business Committee IBC Approved Agency-specific accounting data. Each agency assigns a specific accounting code to an incident.
accrual reports Incident Business Committee IBC Approved Cost reports utilized for financial obligation purposes.
accuracy descriptor (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved Description of the methods used to determine the certainty and precision of the fire location at the point of origin.
action plan National Incident Management System Integration Committee NIMSIC Archived Any tactical plan developed by any element of ICS in support of the incident action plan.
active crown fire Fire Behavior Subcommittee FBSC, IOSC Incident Operations Subcommittee Approved A fire in which a solid flame develops in the crowns of trees, but the surface and crown phases advance as a linked unit dependent on each other.
active fire IOSC Incident Operations Subcommittee Approved Any fire that has not been called "out".
active resources Incident Business Committee IBC Archived Resources checked in and assigned work tasks on an incident.
activity (fire cause) Communication, Education, and Prevention Committee CEPC Approved The thing that a person is doing when a wildland fire ignition occurs.
activity fuels Fire Use Subcommittee FUSC Approved Fuels resulting from, or altered by, forestry practices such as timber harvest or thinning, as opposed to naturally created fuels.
activity group Communication, Education, and Prevention Committee CEPC Approved Further refines wildfire cause supporting data, providing information for prevention programs for targeted messaging.
activity name Communication, Education, and Prevention Committee CEPC Approved Common name of activity
activity name (aviation) Geospatial Subcommittee GSC Approved Common name of the aviation activity.
activity type FRSC Fire Reporting Subcommittee Approved Type of activity or event
activity type (aviation) Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved Type of aviation activity or event
actual completion date Fuels Management Committee FMC Approved Date when treatment was physically completed
Actual Time En Route (ATE) National Interagency Aviation Committee NIAC Approved Term used in flight planning/following to document actual time spent flying between points.
Actual Time of Arrival (ATA) National Interagency Aviation Committee NIAC Approved Term used in flight planning/following to document time of arrival at a point.
Actual Time of Departure (ATD) National Interagency Aviation Committee NIAC Approved Term used in flight planning/following to document time of departure from a point.
adapter Equipment Technology Committee ETC Approved A device for connecting hoses of the same size with non-matching hose threads, or connecting a threaded coupling to a quick-connect coupling.
adiabatic process Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, a process in which a system does not interact with its surroundings by virtue of a temperature difference between them. In an adiabatic process any change in internal energy (for a system of fixed mass) is solely a consequence of working. For an ideal gas and for most atmospheric systems, compression results in warming, expansion results in cooling.
adjective rating Fire Weather Subcommittee FWS Approved A public information description of the relative severity of the current fire danger situation.
Administrative Payment Team (APT) Incident Business Committee IBC Approved A team that supports incident agencies by processing payments for resources. Resources may include emergency equipment, casuals, local vendors for supplies, etc.
Administrative Representative (AR) Incident Business Committee IBC Approved Individual responsible for incident agency business management functions, such as personnel, procurement, fiscal, etc.
administrative workweek Incident Business Committee IBC Approved Period of seven consecutive calendar days designated in advance by the head of a department (5 U.S.C. 6101(a)).
Administratively Determined (AD) Incident Business Committee IBC Approved A person hired and compensated under the Pay Plan for Emergency Workers.
admission Communication, Education, and Prevention Committee CEPC Approved Oral or written statement tending to link its maker to involvement in a particular crime.
adolescent (13-17) Communication, Education, and Prevention Committee CEPC In Development
adult (18+) Communication, Education, and Prevention Committee CEPC In Development
Advanced Life Support (ALS) Risk Management Committee RMC Approved Advanced life support skills performed by an EMS practitioner or service, e.g. intravenous fluids and drug administration.
Advanced Life Support (ALS) Emergency Medical Committee EMC Approved Emergency medical care and interventions performed by an Advanced EMT or Paramedic with limited supervision, using critical thinking and autonomous decision making skills which includes invasive procedures and medication administration.
advancing a line IOSC Incident Operations Subcommittee Approved Moving a hose lay toward a specified area from the point where the hose-carrying apparatus has stopped.
advancing fire Wildland Fire Investigation Subcommittee WFISC Approved That portion of the fire with rapid fire spread with higher intensity which is normally burning with the wind and/or up slope.
advancing front combustion stage Fire Behavior Subcommittee FBSC Approved The period of combustion when a fire is spreading, usually accompanied by flaming combustion that releases heat to sustain the convection column.
advection Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the process of transport of an atmospheric property solely by the mass motion of the atmosphere; also the rate of change of the value of the advected property at a given point.
Advisory Risk Management Committee RMC Approved A time-sensitive alert from an NWCG Committee to the wildland fire community regarding procedural changes, equipment information and/or use updates, potential safety hazards, etc. Yellow hash-marked bordered stationary will be associated with this type of alert.
Adze Hoe Equipment Technology Committee ETC Approved A fire-trenching or digging tool having a sharp, tempered blade, which is useful for heavy grubbing, trenching, and light cutting.
aerial detection IASS Interagency Aerial Supervision Subcommittee Approved A system for, or the act of discovering, locating, and reporting fires from aircraft.
aerial fireworks Communication, Education, and Prevention Committee CEPC In Development Explode or create an aerial flash. The hot remains of an aerial firework may land in flammable vegetation and ignite a fire.    
aerial fuels Fire Use Subcommittee FUSC Approved Standing and supported live and dead combustibles not in direct contact with the ground and consisting mainly of foliage, twigs, branches, stems, cones, bark, and vines.
aerial ignition IOSC Incident Operations Subcommittee, National Interagency Aviation Committee NIAC Approved Ignition of fuels by dropping incendiary devices or materials from aircraft.
Aerial Ignition Device (AID) Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Inclusive term applied to equipment designed to ignite wildland fuels from an aircraft.
aerial reconnaissance IASS Interagency Aerial Supervision Subcommittee Approved Use of aircraft for detecting and observing fire behavior, values-at-risk, suppression activity, and other critical factors to facilitate command decisions on strategy and tactics needed for fire suppression.
aerial torch Interagency Helicopter Operations Subcommittee IHOPS Approved An ignition device suspended under a helicopter, capable of dispensing ignited fuel to the ground for assistance in burning out or backfiring.
affidavit Communication, Education, and Prevention Committee CEPC Approved A statement of declaration in writing and affirmed before an official with authority to administer an oath; a statement of declaration alleging fact to support the issuance of a search or arrest warrant.
After Action Review (AAR) Risk Management Committee RMC Approved A structured review or de-brief process of an event, focused on performance standards, that enables participants to discover for themselves what happened, why it happened, and how to sustain strengths and improve on weaknesses. After action reviews, informal or formal, follow the same general format, involve the exchange of ideas and observations, and focus on improving performance.
agency National Incident Management System Integration Committee NIMSIC Archived An administrative division of a government with a specific function, or a non-governmental organization (e.g., private contractor, business, etc.) that offers a particular kind of assistance. A federal, Tribal, state or local agency that has direct fire management or land management responsibilities or that has programs and activities that support fire management activities.
agency administrator National Incident Management System Integration Committee NIMSIC Approved The official position responsible for the management of a geographic unit or functional area. The managing officer of an agency, division thereof, or jurisdiction having statutory responsibility for incident mitigation and management. Examples: Federal Line Officer, State Forest Officer/Delegate or Fire Manager, Tribal Chairperson, Fire Chief, Police Chief, Sheriff, Mayor or County Representative.
agency certification Incident and Position Standards Committee IPSC Approved The process whereby the employing agency or contractor documents that the individual is fully qualified to perform duties and responsibilities for a specified position.
agency dispatch National Coordination System Committee NCSC, Incident Business Committee IBC Approved The agency or jurisdictional facility from which resources are allocated to incidents.
agency dispatcher National Coordination System Committee NCSC, Incident Business Committee IBC Approved A person working within an agency organization who processes resources to and from incidents.
agency pilot National Interagency Aviation Committee NIAC Approved A federal employee pilot or pilot contracted by a federal agency to fly agency, contracted or leased aircraft. This does not include pilots employed by an aircraft vendor as part of an aircraft services contract, such as airtanker contracts, helicopter contracts or other aircraft contracts.
agency program support (event) National Coordination System Committee NCSC Approved An event, managed by one of the fire agency's other (non-fire) program areas, for accomplishing activities deemed necessary by agency management. 
agency specific costs Incident Business Committee IBC Approved Costs incurred by an agency that address the sole concern of only the agency or are not incurred with mutual benefit. Agency specific costs are not shared.
air accident (event) Approved An event dealing with an accident or mishap involving aircraft.
air ambulance Risk Management Committee RMC Approved A rotary wing aircraft configured, staffed and equipped to respond, care for and transport a patient(s) and approved/licensed by a state to do so. An air ambulance is sometimes referred to as a medevac.
air attack National Interagency Aviation Committee NIAC Approved The deployment of fixed-wing or rotary aircraft on a wildland fire, to drop retardant or extinguishing agents, shuttle and deploy crews and supplies, or perform aerial reconnaissance of the overall fire situation.
air attack base National Interagency Aviation Committee NIAC Approved Permanent facility at which aircraft are stationed for use in air attack operations.
air cargo National Interagency Aviation Committee NIAC Approved All items for transport and delivery by aircraft.
air contaminant Fire Use Subcommittee FUSC Approved An airborne dust, fume, gas, mist, odor, smoke, vapor, soot, pollen, carbon, acid or particulate matter or any combination thereof.
air crew member National Interagency Aviation Committee NIAC In Development Additional crew member required for accomplishment of the mission such as flight attendant, smokejumper/rappel spotter, cargo loadmaster, helicopter manager, etc. These positions usually do not require any Airman Certificate(s) or a flight physical. Referred to as a Qualified Non-Crew Member in the CFR.
air guard National Coordination System Committee NCSC Approved A common VHF-FM frequency used by natural resource agency aircraft for emergency radio transmissions.
air mass Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, a widespread body of air that is approximately homogeneous in its horizontal extent, particularly with reference to temperature and moisture distribution; in addition, the vertical temperature and moisture variations are approximately the same over its horizontal extent.  The properties of the air mass are established while that air was situated over a particular region of the earth's surface.
air pack Risk Management Committee RMC Approved Portable air (not oxygen) tanks with regulators which allow firefighters to breathe while in toxic smoke conditions. Usually rated for 30 minutes of service. Used primarily on fires involving structures or hazardous materials.
air pollution Fire Use Subcommittee FUSC Approved The general term referring to the undesirable addition of substances (gases, liquids, or solid particles) to the atmosphere that are foreign to the natural atmosphere or are present in quantities exceeding natural concentrations.
air pollution alert Fire Use Subcommittee FUSC Approved A statement issued by an Air Quality Regulatory Agency due to high measured concentrations of pollutants. The alert remains in effect until monitoring shows a decrease in pollutant levels. Should conditions worsen, air pollution warnings and emergencies may be issued. At each stage (alert, warning and emergency) additional emission restrictions are put into effect so as to not intensify the situation. Essentially, at the emergency level all industrial activities and auto usage stop. 
air quality Fire Use Subcommittee FUSC Approved The composition of air with respect to quantities of pollution therein; used most frequently in connection with "standards" of maximum acceptable pollutant concentrations. Used instead of "air pollution" when referring to programs.
air quality model Fire Use Subcommittee FUSC Approved Mathematical or quantitative representation or simulation of air quality processes; e.g., emission models, receptor models, or air quality dispersion models.
Air Stagnation Advisory (ASA) Fire Weather Subcommittee FWS Approved A statement issued by a National Weather Service forecast office when atmospheric conditions are stable enough such that the potential exists for air pollutants to accumulate in a given area. The statement is initially issued when conditions are expected to last for at least 36 hours. 
aircraft (specific cause) Communication, Education, and Prevention Committee CEPC In Development An airplane, helicopter, or other machine capable of flight.
aircraft accident National Interagency Aviation Committee NIAC Approved An unplanned event that does substantial damage or causes serious injuries when associated with the operation of applicable aircraft. Event occurs between the time engine(s) is (are) started or rotors turning for the purpose of commencing flight, until the aircraft comes to rest with engines and propellers or rotors stopped, the brakes set or wheel chocks in place, and all persons have disembarked. 
aircraft data card National Interagency Aviation Committee NIAC Approved Card or documentation required to be on board the aircraft which approves use and indicates specific types of use.
aircraft footprint National Interagency Aviation Committee NIAC Approved That area on the surface of the earth, runway, or ramp that is covered by the tread of the aircraft tire while the aircraft is motionless.
aircraft ground mishap National Interagency Aviation Committee NIAC Approved An aircraft mishap in which there is no intent to fly. However, the power plants and/or rotors are in operation and damage is incurred requiring replacement or repair of rotors, propellers, wheels, tires, wing tips, flaps, etc., or injury is incurred requiring first-aid or medical attention.
aircraft incident National Interagency Aviation Committee NIAC Approved An unplanned event that results in damage which is less than serious aircraft incident criteria, or injuries not requiring medical attention.
Aircraft Network (AirNet) National Coordination System Committee NCSC Approved Applies to radio frequencies primarily used for air operations.
airtanker National Interagency Aviation Committee NIAC Approved Fixed-wing aircraft certified by FAA as being capable of transport and delivery of fire retardant solutions.
Alert System Risk Management Committee RMC Approved A method used to distribute various types of general or time-sensitive information from an NWCG committee to the wildland fire community. Information may include bulletins, advisories, or safety warnings, each with an associated color hash-marked bordered stationary.
alidade Equipment Technology Committee ETC Approved A sighting device used by lookouts to determine the horizontal bearing and sometimes the vertical angle of a fire from a lookout.
all hazard incident National Incident Management System Integration Committee NIMSIC Approved A threat or an incident, natural or manmade, that warrants action to protect life, property, the environment, and public health or safety, and to minimize disruptions of government, social, or economic activities. It includes natural disasters, cyber incidents, industrial accidents, pandemics, acts of terrorism, sabotage, and destructive criminal activity targeting critical infrastructure. This also includes the effects climate change has on the threats and hazards.
All Hazards Meteorological Response System (AMRS) Fire Weather Subcommittee FWS Approved A mobile weather data collection and forecasting system consisting of a communications module, weather observing module, and data interigation module. Used by incident meteorologists on an incident.
All Terrain Vehicle (ATV) Equipment Technology Committee ETC Approved Any motorized vehicle designed for or capable of cross-country travel on or immediately over land, water, sand, snow, ice, marsh, swampland, or other terrain.
alligatoring Communication, Education, and Prevention Committee CEPC Approved Char patterns formed on paint or burned wood remains, usually in the shape of blisters.
allocated resources Incident Business Committee IBC Archived Resources dispatched to an incident, that have not yet checked in.
allowable payload National Interagency Aviation Committee NIAC Approved The amount of weight that is available for passengers and/or cargo. On the load calculation form it is the operating weight subtracted from the selected weight.
altimeter setting National Interagency Aviation Committee NIAC Approved The barometric pressure reading used to adjust a pressure altimeter for variations in existing atmospheric pressure or to the standard altimeter setting (29.92) inches.
ambient air Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, background, environmental, or surrounding air.
ambulance Risk Management Committee RMC Approved A ground transport vehicle configured, equipped and staffed to respond, care for and transport a patient(s) and approved by a state to do.
anchor point IOSC Incident Operations Subcommittee Approved An advantageous location, usually a barrier to fire spread, from which to start constructing a fireline. The anchor point is used to minimize the chance of being flanked by the fire while the line is being constructed.
anemometer Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the general name for instruments designed to measure total wind speed.
annual certification Incident and Position Standards Committee IPSC Approved Annual review by an employing agency of an individual's position qualifications and documentation certifying that the individual is fully qualified to perform duties and responsibilities for a specified position. Annual certification is based on established performance standards and agency specific requirements. 
Annual Operating Plan (AOP) [fire weather] Fire Weather Subcommittee FWS Approved A procedural guide which describes fire meteorological services provided within the Geographic Area of responsibility, including the National Interagency Fire Center. The guide is based on the National Interagency Agreement and applicable Geographic Area Memorandum of Agreement. 
annual plant FDSC Fire Danger Subcommittee Approved A plant that lives for one growing season, starting from a seed each year.
anticyclone Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, an atmospheric anticyclonic circulation, a closed circulation. The wind in an anticyclone is in the clockwise direction in the Northern Hemisphere.
apparatus Equipment Technology Committee ETC Approved A motor-driven vehicle, or group of vehicles, designed and constructed for the purpose of fighting fires. May be of different types such as engines, water tenders, ladder trucks, etc.
apparatus identifier Equipment Technology Committee ETC Approved The alphanumeric characters assigned to an apparatus.
apparatus number National Coordination System Committee NCSC Archived The external alphanumeric value painted on the side of the equipment.
approved IOSC Incident Operations Subcommittee Archived In fire service terminology, that which is inspected and listed by recognized fire-testing agencies. The term as used in National Fire Protection Association standards means approval by the authority having jurisdiction, such as the fire chief, insurance inspection department, or other agency that enforces standards or regulations. 
Aramid Risk Management Committee RMC Approved The generic name for a high-strength, flame-resistant, synthetic fabric used in the shirts and jeans of firefighters. Nomex ® , a brand name for aramid fabric, is the term commonly used by firefighters.
arduous (duty level) Risk Management Committee RMC Archived Arduous duty field work requires above-average endurance and superior conditioning.  Duties may include an occasional demand for extraordinarily strenuous activity in emergency situations under adverse environmental conditions over extended periods. The pace of work typically is set by the emergency condition.  Essential functions include, but are not limited to: running, walking or hiking, climbing, jumping, twisting, bending, lifting more than 50 pounds, and carrying 45 pounds or more for extended periods over difficult terrain. 
area command National Incident Management System Integration Committee NIMSIC Approved An organization that oversees the management of multiple incidents or oversees the management of a very large or evolving situation with multiple ICS organizations.
area coordination center National Coordination System Committee NCSC, Incident Business Committee IBC Approved A facility which serves as a central point for one or more agencies to use in processing information and resource requests. It may also serve as a dispatch center for one of the agencies.
area ignition Fire Use Subcommittee FUSC Approved Ignition of several individual fires throughout an area, either simultaneously or in rapid succession, and so spaced that they add to and influence the main body of the fire to produce a hot, fast-spreading fire condition.
area of influence IOSC Incident Operations Subcommittee Approved Delineated area surrounding a base which can be reached first by the ground or air attack units assigned to the base.
area source Fire Use Subcommittee FUSC Approved A source category of air pollution that generally extends over a large area. Prescribed burning, field burning, home heating, and open burning are examples of area sources.
armed SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved A term used to indicate that the airtanker dropping mechanism is set to allow a programmed release of part or all of the load of fire retardant.
arrest Wildland Fire Investigation Subcommittee WFISC Approved The taking or keeping of a person in custody by legal authority, especially in response to a criminal charge.
arson Wildland Fire Investigation Subcommittee WFISC Approved At common law, the malicious and willful burning of another's dwelling, outhouse or parcel; by most modern statutes, the intentional and wrongful burning of someone else's, or one's own, property. Frequently requires proof of malicious or wrongful intent.
arson Communication, Education, and Prevention Committee CEPC In Development At common law, the malicious and willful burning of another's dwelling, outhouse, or parcel; by most modern statutes, the intentional or wrongful burin gof someone else's, orone's own property. Frequently requires proof of malicious or wrongful intent.
arson fire Wildland Fire Investigation Subcommittee WFISC Approved A fire that is intentional and wrongfully set to burn one's own or someone else's property.
arson task force Wildland Fire Investigation Subcommittee WFISC Approved Group of individuals convened to analyze, investigate and solve arson problems in a particular region.
arsonist Wildland Fire Investigation Subcommittee WFISC Approved One who commits arson.
aspect FDSC Fire Danger Subcommittee Approved Cardinal direction toward which a slope faces.
aspect code (Point of Origin) (POO) Geospatial Subcommittee GSC Approved A code used to describe the direction toward which the predominant slope faces at the point of origin of the fire (including ridgetops and/or flat ground). Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
aspirate [foam] Equipment Technology Committee ETC Approved To draw in gases (or other substances); nozzle aspirating systems draw air into the nozzle to mix with the foam solution.
assessment [decision-making] Incident Business Committee IBC Approved The evaluation and interpretation of measurements, intelligence, and other information to provide a basis for decision-making.
assessment [fire weather] Fire Weather Subcommittee FWS Approved A fire weather fire danger product based on a thorough evaluation of all pertinent sources of meteorological, fire danger and resource information.
assigned resources National Incident Management System Integration Committee NIMSIC Approved Resources checked in and assigned work tasks on an incident.
assignments National Incident Management System Integration Committee NIMSIC Approved A task given to a person or team to perform based on operational objectives defined in the IAP.
assistant National Incident Management System Integration Committee NIMSIC Approved A title for subordinates of principal Command Staff and EOC director’s staff positions. The title indicates a level of technical capability, qualification, and responsibility subordinate to the primary positions. Assistants may also be assigned to unit leaders.
assisting agency National Incident Management System Integration Committee NIMSIC, Incident Business Committee IBC Approved An agency or organization providing personnel, services, or other resources to the agency with direct responsibility for incident management.
assumption Wildland Fire Investigation Subcommittee WFISC Approved Acceptance of information as true without proof or demonstration.
asynchronous (training) Training Delivery Committee TDC Approved Training where the students and/or instructors are not interacting with each other in real time. Typically, the students are accessing learning resources at a time of their choosing.
at incident National Coordination System Committee NCSC Proposed New The resource is committed and at the assigned incident.
atmometer Fire Environment Committee FENC Approved An instrument that provides an approximate measure of evapotranspiration by measuring the water loss from an artificial evaporating surface.
atmospheric inversion Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, a departure from the usual decrease or increase with altitude of the value of an atmospheric property; also, the layer through which this departure occurs (the "inversion layer"), or the lowest altitude at which the departure is found ("the base of the inversion"). In fire management usage, nearly always refers to an increase in temperature with increasing height.
atmospheric pressure Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the net force per unit area exerted by the atmosphere as a consequence of gravitational attraction exerted upon the column of air lying directly above the point in question.  Atmospheric pressure is independent of the orientation of the surface on which it acts.
atmospheric stability Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the ability of the atmosphere at rest to become turbulent or laminar due to the effects of buoyancy. Air tending to become or remain turbulent is said to be statically unstable; one tending to become or remain laminar is statically stable; and one on the borderline between the two (which might remain laminar or turbulent depending on its history) is statically neutral.
attack a fire IOSC Incident Operations Subcommittee Approved Limit the spread of fire by any appropriate means.
attack line IOSC Incident Operations Subcommittee Approved A line of hose, preconnected to the pump of a fire apparatus and ready for immediate use in attacking a fire. Contrasted to supply lines connecting a water supply with a pump or to feeder lines extended from a pump to various points around the perimeter of a fire. 
attack time IOSC Incident Operations Subcommittee Approved The starting date, hour, and minute of the first suppression work on a fire.
attack unit IOSC Incident Operations Subcommittee Approved Single vehicle or aircraft and its associated personnel and material provided for the purpose of responding to and abating a fire or other emergency.
attack unit response IOSC Incident Operations Subcommittee Approved The response of one attack unit to a fire or other emergency with no regard for the number of return trips to that same fire or emergency.
attainment area Fire Use Subcommittee FUSC Approved An area considered to have air quality as good as, or better than, the National Ambient Air Quality Standards (NAAQS) as defined in the Clean Air Act. An area may be in attainment for one or more pollutants but be in nonattainment for one or more other pollutants. 
authority having jurisdiction National Incident Management System Integration Committee NIMSIC Approved An organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.
authorized passenger National Interagency Aviation Committee NIAC Approved Passengers may be transported in government aircraft only if they meet definition of an Official or an Unofficial Passenger.
Automatic Weather Station (AWS) FDSC Fire Danger Subcommittee Approved A non-GOES telemetered weather station that provides hourly observations to a local database.
automatically regulated IABS Interagency Airtanker Base Subcommittee Approved A proportioning method or device that readily adjusts to changes in water flow and or pressure to maintain a desired mix ratio.
autorotation National Interagency Aviation Committee NIAC Approved A helicopter flight condition in which the lifting rotor is driven entirely by action of air when the helicopter is in motion.
auxiliary pump Equipment Technology Committee ETC Approved A secondary pump on an engine in addition to the main pump. Usually of small capacity.
available Proposed New The resource can be used to fill a request. Resources on preposition incidents qualify as available.
available fuel Fire Use Subcommittee FUSC Approved That portion of the total fuel that would actually burn under various environmental conditions.
available resources National Incident Management System Integration Committee NIMSIC Approved Resources assigned to an incident and available for assignment.
average annual precipitation FDSC Fire Danger Subcommittee Approved The expected amount of annual rainfall. Average annual precipitation is an important component to determining the Keech-Bryam Drought Index (KBDI).
average relative humidity FDSC Fire Danger Subcommittee Approved The mathematical average of the maximum and minimum relative humidities measured at a fire weather station from one basic observation time to the next.
average temperature Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the average temperature of the air as indicated by a properly exposed thermometer during a given time period, usually a day, a month, or a year.
aviation activity point Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved A geospatial layer reference to activities that that may present a hazard to pilots during aviation operations displayed as a point.
aviation activity polygon Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved A geospatial layer reference to activities that that may present a hazard to pilots during aviation operations displayed as a polygon.
aviation call sign National Interagency Aviation Committee NIAC Approved Communication call sign assigned as a unique identifier to an aircraft.
aviation obstruction line Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved A geospatial reference to physical features that may present a hazard to pilots during aviation operations displayed as a line.
aviation obstruction point Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved A geospatial reference to physical features that may present a hazard to pilots during aviation operations displayed as a point.
aviation obstruction polygon Geospatial Subcommittee GSC, National Interagency Aviation Committee NIAC Approved A geospatial reference to physical features that may present a hazard to pilots during aviation operations displayed as a polygon.
avoidance Fire Use Subcommittee FUSC Approved A smoke emission control strategy that considers meteorological conditions when scheduling prescribed fires in order to avoid incursions into smoke sensitive areas.
awareness IOSC Incident Operations Subcommittee Archived The continual process of collecting, analyzing, and disseminating intelligence, information, and knowledge to allow organizations and individuals to anticipate requirements and to react effectively and safely.
azimuth [measurement technique] Wildland Fire Investigation Subcommittee WFISC Approved Horizontal angle or bearing of a point measured clockwise from true (astronomic) north.
azimuth circle IOSC Incident Operations Subcommittee Archived A circle graduated in 360 degrees in a clockwise direction from true (astronomic) north.
back azimuth IOSC Incident Operations Subcommittee Archived Angle or bearing 180 degrees opposite of azimuth.
back bearing External Source Approved A back bearing is measured from the object to your position. It is the exact opposite of a direct bearing.
backburn Fire Use Subcommittee FUSC Approved Used in some localities to specify fire set to spread against the wind in prescribed burning.
backdraft Fire Use Subcommittee FUSC Approved Instantaneous explosion or rapid burning of superheated gases that occurs when oxygen is introduced into an oxygen-depleted confined space. It may occur because of inadequate or improper ventilation procedures.
backfire Fire Use Subcommittee FUSC Approved A fire set along the inner edge of a fireline to consume the fuel in the path of a wildfire or change the direction of force of the fire's convection column.
backfire torch Equipment Technology Committee ETC Approved A flame generating device (e.g., a fount containing diesel oil or kerosene and a wick, or a backpack pump serving a flame-jet).
backfiring Fire Use Subcommittee FUSC Approved A tactic associated with indirect attack, intentionally setting fire to fuels inside the control line to slow, knock down, or contain a rapidly spreading fire. Backfiring provides a wide defense perimeter and may be further employed to change the force of the convection column. Backfiring makes possible a strategy of locating control lines at places where the fire can be fought on the firefighter's terms. Except for rare circumstance meeting specified criteria, backfiring is executed on a command decision made through line channels of authority. 
background level Fire Use Subcommittee FUSC Approved In air pollution control, the concentration of air pollutants in a definite area during a fixed period of time prior to the starting up, or the stoppage, of a source of emission under control. In toxic substances monitoring, the average presence in the environment, originally referring to naturally-occurring phenomena. 
backing fire Wildland Fire Investigation Subcommittee WFISC, Fire Use Subcommittee FUSC Approved That portion of the fire with slower rates of fire spread and lower intensity normally moving into the wind and/or down slope.
backing fire [spread] Wildland Fire Investigation Subcommittee WFISC, Fire Use Subcommittee FUSC Approved Fire spreading, or ignited to spread, into (against) the wind or downslope. A fire spreading on level ground in the absence of wind is a backing fire.
backing wind Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, in the Northern Hemisphere, a wind that rotates in the counterclockwise direction with increasing height. In fire management usage, in the Northern Hemisphere, a wind that rotates in the counterclockwise direction over a given time period (normally a few hours).
backpack pump Equipment Technology Committee ETC Approved A portable sprayer with hand-pump, fed from a liquid filled container fitted with straps, used mainly in fire and pest control.
baffle Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A partitioned wall placed in vehicular or aircraft water tanks to reduce shifting of the water load when starting, stopping or turning.
ball valve Equipment Technology Committee ETC Approved A valve in which fluid flow is controlled by a ball with a hole drilled through it. In one position, fluid flows through the hole. When the valve is turned 90 degrees (1/4 turn) the hole is perpendicular to the flow and the ball stops the flow. Intermediate valve positions can be used to adjust the flow. 
Bambi Bucket National Interagency Aviation Committee NIAC Approved A collapsible bucket slung below a helicopter. Used to dip water from a variety of sources for fire suppression.
bandwidth RSUSC Wildland Fire Radio Standards and Use Committee Approved The efficiency technology of either 25 KHz or 12.5 KHz in the frequency bands within the UHF/VHF ranges.
banking snags IOSC Incident Operations Subcommittee Approved The act of throwing mineral soil about the base of an unlighted snag to prevent its being ignited by a surface fire.
barbeque/smoker Communication, Education, and Prevention Committee CEPC In Development
barometer Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, an instrument for measuring atmospheric pressure.
barometric pressure FDSC Fire Danger Subcommittee Approved Atmospheric pressure corrected for elevation.
barrier IOSC Incident Operations Subcommittee Approved Any obstruction to the spread of fire. Typically an area or strip devoid of combustible fuel.
base [incident] National Incident Management System Integration Committee NIMSIC Approved A location where personnel coordinate and administer logistics functions for anincident. There is typically only one base per incident. (An incident name or other designator is added to the term Base.) The ICP may be co-located with the Incident Base.
base [initial attack] National Incident Management System Integration Committee NIMSIC Approved The location of initial attack forces.
base area FDSC Fire Danger Subcommittee Approved An area representative of the major fire problems on a protection unit. Base fuel model and slope class are chosen from the base area.
base fuel model FDSC Fire Danger Subcommittee Approved A representation of the vegetative cover and fuel in a base area. Used in the calculation of fire danger rating.
base hours Incident Business Committee IBC Approved The number of hours in a daily tour of duty.
base line External Source An imaginary line on the ground running east-west (horizontal) measured with special accuracy to provide a base for surveying.
base observation time FDSC Fire Danger Subcommittee Approved The time established to take the fire danger observations. It should be at the time of day when the fire danger is normally the highest. The usually agreed upon time is 1:00 pm standard time. This allows time to transmit observations and prepare forecasts. 
base station National Coordination System Committee NCSC Approved A fixed central radio dispatching station controlling movements of one or more mobile units.
baseline Fuels Management Committee FMC Approved In prescribed burning, the initial line of fire, usually set as a backing fire along a barrier or control line, which serves to contain subsequent burning operations.
Basic Life Support (BLS) Risk Management Committee RMC Approved Basic life support skills performed by an EMS practitioner or service, e.g. splinting, bandaging, oxygen administration, use of the AED.
basic workweek Incident Business Committee IBC Approved Refers to the scheduled workweek of the employee (individual) at the home unit.
batch mix Equipment Technology Committee ETC Approved Manually adding and mixing a concentrated chemical, such as liquid foam, or powdered or liquid retardant with water, or gelling agents with fuel, into solution in a tank or container.
bearing IOSC Incident Operations Subcommittee Archived The horizontal direction to or from any point, usually measured clockwise from true north, or some other reference point through 360 degrees.
Beaufort Wind Scale Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, a system of estimating and reporting wind speeds using a numerical scale ranging from 0 (calm) to 12 (hurricane).
BEHAVE Fire Behavior Subcommittee FBSC Archived A system of interactive computer programs for modeling fuel and fire behavior, comprised of two systems: BURN and FUEL. 
behavior Incident and Position Standards Committee IPSC Approved An observable activity or action demonstrated by an individual in a particular context.
belt weather kit Fire Weather Subcommittee FWS, Equipment Technology Committee ETC Approved Belt-mounted case with pockets fitted for anemometer, compass, sling psychrometer, slide rule, water bottle, pencils, and book of weather report forms. Used to take weather observations to provide on-site conditions to the fire weather forecaster or fire behavior analyst. Observations include air temperature, wind speed and direction, and relative humidity. 
benefits FMB Fire Management Board Approved Something that represents, promotes or enhances a desired outcome, being of positive value and contributing to the attainment of organizational goals. Benefits represent one end of the spectrum of outcomes from fire, with the opposite end being harm, loss or damage. 
berm IOSC Incident Operations Subcommittee Approved A ridge of soil and debris along the outside edge of a fireline, resulting from line construction.
Best Available Control Measures (BACM) Fire Use Subcommittee FUSC Approved An emission limitation action based on the maximum degree of emission reduction (considering energy, environmental, and economic impacts) achievable through application of production processes and available methods, systems, and techniques.
billable/reimbursable costs Incident Business Committee IBC Approved Those agency costs that are billable and/or reimbursable as defined by the master or individual cost share agreement.
biological or toxic conditions (event) National Coordination System Committee NCSC Approved An event dealing with the hazardous situations that arise as with the presence of biological hazards and/or deadly chemicals. This category includes chemical spills/leaks, deliberate poisoning, chemical accident, animal/plant disease outbreak, biohazard exposure, etc.
birth month day National Coordination System Committee NCSC Approved The birth month and day for the overhead resource.
black powder/muzzle loading Communication, Education, and Prevention Committee CEPC In Development
blackline Fire Use Subcommittee FUSC Approved Preburning of fuels adjacent to a control line before igniting a prescribed burn. Blacklining is usually done in heavy fuels adjacent to a control line during periods of low fire danger to reduce heat on holding crews and lessen chances for spotting across control line. In fire suppression, a blackline denotes a condition where there is no unburned material between the fireline and the fire edge.
bladder bag Equipment Technology Committee ETC Approved A collapsible backpack portable sprayer made of neoprene or high-strength nylon fabric fitted with a pump.
blasting Communication, Education, and Prevention Committee CEPC In Development
blended training Training Delivery Committee TDC Approved Training that is specifically designed to meet course objectives through a combination of self-directed online training and Instructor-led training. The online component typically contains a portion of the curriculum content and must be successfully completed in order to complete the course.
blind area IOSC Incident Operations Subcommittee Approved An area in which neither the ground nor its vegetation can be seen from a given observation point.
block plan Fire Use Subcommittee FUSC Approved A detailed prescription for treating a specified burning block with fire.
blowup Fire Weather Subcommittee FWS Approved Sudden increase in fireline intensity or rate of spread of a fire sufficient to preclude direct control or to upset existing suppression plans. Often accompanied by violent convection and may have other characteristics of a fire storm.
board of review Risk Management Committee RMC Approved A board or committee selected to review results of fire suppression action on a given unit or the specific action taken on a given fire. The board reviews the results in order to identify reasons for both good and poor action and to recommend or prescribe ways and means of doing an effective and efficient job. Reviews the results of a safety/accident investigation. 
Boiling Liquid Expanding Vapor Explosion (BLEVE) [failure] IOSC Incident Operations Subcommittee Approved The failure of a closed container as a result of overpressurization caused by an external heat source.
Boiling Liquid Expanding Vapor Explosion (BLEVE) [major failure] IOSC Incident Operations Subcommittee Approved A major failure of a closed liquid container into two or more pieces when the temperature of the liquid is well above its boiling point at normal atmospheric pressure.
bole Hazard Tree and Felling Subcommittee HTTFS Approved The trunk of a tree.
bone yard [area] IOSC Incident Operations Subcommittee Approved An area cleared to mineral soil for piling unburned fuels.
bone yard [mop up] IOSC Incident Operations Subcommittee Approved A mop up term. To "bone yard" a fire means to systematically work the entire area, scraping embers off remaining fuel, feeling for heat with the hands, and piling unburned materials in areas cleared to mineral soil.
bonfire/party fire Communication, Education, and Prevention Committee CEPC In Development
booster hose Equipment Technology Committee ETC Approved The most common type of hose attached and stored on wildland engine booster reels. The hose is made of neoprene and does not appreciably collapse when stored empty.
booster pump Equipment Technology Committee ETC Approved An intermediary pump for supplying additional lift in pumping water uphill past the capacity of the first pump.
booster reel Equipment Technology Committee ETC Approved A reel for the booster hose mounted on a fire engine, often supplied by the auxiliary pump. This reel usually carries a 1-inch (25 mm) or 3/4 inch (19 mm) hose and frequently contains an electric rewind mechanism.
border fire National Coordination System Committee NCSC Approved A border fire is any wildland fire that has crossed or threatens to cross established Dispatch Boundaries. Dispatch Boundaries include local and geographic area boundaries and are established in the National Dispatch Boundary and National GACC Boundary geospatial data sets.
boundary conditions FDSC Fire Danger Subcommittee Approved The temperature and relative humidity of the boundary layer.
boundary layer [air] Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the layer of air near a boundary that is affected by friction against that boundary surface, and possibly by transport of heat and other variables across that surface.
boundary layer [atmospheric] Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the bottom layer of the troposhpere that is in contact with the surface of the earth. It is often turbulent and is capped by a statically stable layer of air or temperature inversion.
boundary value FDSC Fire Danger Subcommittee Approved The equilibrium moisture content (EMC) commensurate with the boundary conditions and precipitation events of the preceding 24 hours.
Bowles Bag National Interagency Aviation Committee NIAC Approved A neoprene tank designed for attachment to the landing skid frame of a helicopter. It has a capacity of 80 to 100 gallons (303 to 378 liters) of water or retardant.
box canyon Fire Environment Committee FENC Approved A steep-sided, dead end canyon.
brakes Communication, Education, and Prevention Committee CEPC In Development A mechanical system used to slow down, stop or control the motion of a moving object by applying friction or force.
Branch National Incident Management System Integration Committee NIMSIC Approved The organizational level having functional or geographical responsibility for major aspects of incident operations. A Branch falls between the Section Chief and the division or group in the Operations Section, and between the section and units in the Logistics Section. Branches are identified by Roman numerals or by functional area.
branding Communication, Education, and Prevention Committee CEPC In Development the action of marking/burning with a branding iron
break a line IOSC Incident Operations Subcommittee Approved To insert a gate valve or some other device into a hose line.
break coupling Equipment Technology Committee ETC Approved To detach two pieces of hose by backing the swivel thread off the nipple thread.
break left or right National Interagency Aviation Committee NIAC Approved Means "turn" left or right. Applies to aircraft in flight, usually on the drop run, and when given as a command to the pilot, implies expectation of prompt compliance.
breakover Incident and Position Standards Committee IPSC Archived A fire edge that crosses a control line or natural barrier intended to confine the fire.
British Thermal Unit (Btu) Fire Behavior Subcommittee FBSC Approved Amount of heat required to raise 1 pound of water 1 degree Fahrenheit (from 59.50 to 60.50 F), measured at standard atmospheric pressure.
broadcast burning Fire Use Subcommittee FUSC Approved Prescribed burning activity where fire is applied generally to most or all of an area within well defined boundaries for reduction of fuel hazard, as a resource management treatment, or both.
brown and burn Fire Use Subcommittee FUSC Approved Application of herbicide to desiccate living vegetation prior to burning.
brownspot control Fire Use Subcommittee FUSC Approved Prescribed fire to control fungal infection (brown spot disease) of longleaf pine (Pinus palustris) in the "grass" (small seedling) stage.
brush Fire Use Subcommittee FUSC Approved A collective term that refers to stands of vegetation dominated by shrubby, woody plants, or low growing trees, usually of a type undesirable for livestock or timber management.
brush blade Equipment Technology Committee ETC Approved Blade attachment with long teeth specially suited to ripping and piling brush with minimum inclusion of soil.
brush fire IOSC Incident Operations Subcommittee Approved A fire burning in vegetation that is predominantly shrubs, brush, and scrub growth.
brush hook Equipment Technology Committee ETC Approved A heavy cutting tool designed primarily to cut brush at the base of the stem. Used in much the same way as an axe and having a wide blade, generally curved to protect the blade from being dulled by rocks.
brush management Fire Use Subcommittee FUSC Approved Manipulation of stands of brush by manual, mechanical, chemical, or biological means or by prescribed burning for the purpose of achieving land management objectives.
brush patrol unit Equipment Technology Committee ETC Approved Any light, mobile vehicular unit with limited pumping and water capacity for off-road operations.
bubble Equipment Technology Committee ETC Approved The building block of foam; bubble characteristics of water content and durability influence foam performance.
bucket drops National Interagency Aviation Committee NIAC Approved The dropping of fire retardants or suppressants from specially designed buckets slung below a helicopter.
bucking Hazard Tree and Felling Subcommittee HTTFS Approved Sawing through the bole of a tree after it has been felled.
build-up [fire danger] FDSC Fire Danger Subcommittee Approved The cumulative effects of long-term drying on current fire danger.
build-up [fire management] IOSC Incident Operations Subcommittee Approved The increase in strength of a fire management organization.
build-up [fire spread] FDSC Fire Danger Subcommittee Approved The accelerated spreading of a fire with time.
build-up [weather] Fire Weather Subcommittee FWS Approved Towering cumulus clouds which may lead to thunderstorms later in the day.
Buildup Index (BUI) FDSC Fire Danger Subcommittee Approved A relative measure of the cumulative effect of daily drying factors and precipitation on fuels with a ten-day timelag.
bulk density IOSC Incident Operations Subcommittee Archived Weight per unit volume. For fuels, this is usually expressed as pounds per cubic foot; for soils, grams per cubic centimeter.
Bulletin Risk Management Committee RMC Approved A general alert from an NWCG committee to the wildland fire community regarding the release of subject-specific information such as technical information, equipment updates, accident reports, etc. Depending on the origin and/or the subject content, a green hash-marked bordered stationary may be associated with this type of alert.
bumpup method IOSC Incident Operations Subcommittee Approved Progressive method of fireline construction on a wildfire without changing relative positions in the line. Work is begun with a suitable space between workers; whenever one worker overtakes another, all of those ahead move one space forward and resume work on the uncompleted part of the line. The last worker does not move ahead until work is completed in his/her space. Forward progress of the crew is coordinated by a crew boss. 
burn (ongoing) IOSC Incident Operations Subcommittee Approved A fire in progress or under investigation.
burn [area] IOSC Incident Operations Subcommittee Approved An area burned over by wildland fire.
burn [consumption] IOSC Incident Operations Subcommittee Approved To consume fuel during rapid combustion.
burn [fire] IOSC Incident Operations Subcommittee Approved A reference to a working fire.
burn [injury] Risk Management Committee RMC Approved An injury to flesh caused by a cauterizing agent, heat from a fire, or a heated object.
burn [on fire] IOSC Incident Operations Subcommittee Approved To be on fire.
burn barrel Communication, Education, and Prevention Committee CEPC In Development Fuels burned within a barrel.
burn block Fire Use Subcommittee FUSC Approved A discrete area within a larger prescribed or fire use project.
burn out Fire Use Subcommittee FUSC Approved Setting fire inside a control line to consume fuel between the edge of the fire and the control line.
burn out time Fire Use Subcommittee FUSC Approved The duration of flaming and smoldering combustion phases at a specified point within a burn or for the whole burn, expressed in convenient units of time.
burn patterns (configuration) Fire Use Subcommittee FUSC Approved The characteristic configuration of char left by a fire. In wildland fires burn patterns are influenced by topography, wind direction, length of exposure, and type of fuel. Definitions are scale-dependent: (1) They can be used to trace a fire's origin; (2) They are influenced by severity and intensity within a stand; (3) They describe the landscape mosaic.
burn patterns (design) Wildland Fire Investigation Subcommittee WFISC Approved Apparent and obvious design of burned material and the burning path from the area of origin.
burn severity Fire Weather Subcommittee FWS Approved A qualitative assessment of the heat pulse directed toward the ground during a fire. Burn severity relates to soil heating, large fuel and duff consumption, consumption of the litter and organic layer beneath trees and isolated shrubs, and mortality of buried plant parts. 
Burned Area Emergency Response Team (BAER Team) Incident Business Committee IBC Approved BAER teams are formed to analyze post-fire conditions and to take immediate emergency stabilization action to prevent loss of life and property and critical and natural resources. It is the Agency Administrator’s responsibility to order or designate a BAER Team.
burned area rehabilitation FMB Fire Management Board Approved The post-fire activities prescribed and implemented to rehabilitate and restore fire damaged lands.
burning Wildland Fire Investigation Subcommittee WFISC Approved Decomposition of material by the application of heat and oxidation. Also applied to propellants and other pyrotechnic mixtures, though the proper term there is "reacting". Also often an element of the crime of arson.
burning ban Fire Use Subcommittee FUSC Approved A declared ban on open air burning within a specified area, usually due to sustained high fire danger.
burning conditions Fire Use Subcommittee FUSC Approved The state of the combined factors of the environment that affect fire behavior in a specified fuel type.
burning index (fire behavior) FDSC Fire Danger Subcommittee Approved A relative number related to the contribution that fire behavior makes to the amount or effort needed to contain a fire in a specified fuel type. Doubling the burning index indicates that twice the effort will be required to contain a fire in that fuel type as was previously required, providing all other parameters are held constant. 
burning index (flame length) FDSC Fire Danger Subcommittee Approved An estimate of the potential difficulty of fire containment as it relates to the flame length at the head of the fire.
burning index meter Fire Behavior Subcommittee FBSC Approved A device used to determine the burning index for different combinations of burning index factors.
burning out IOSC Incident Operations Subcommittee Approved Setting fire inside a control line to consume fuel located between the edge of the fire and the control line.
burning period Fire Behavior Subcommittee FBSC Approved That part of each 24-hour period when fires spread most rapidly; typically from 10:00 AM to sundown.
burning personal items Communication, Education, and Prevention Committee CEPC In Development lighting personal items on fire, in the open, in order for the fire to consume them (not in a burn barrel)
burning priority rating Fire Use Subcommittee FUSC Approved System of rating slash to indicate the treatment objective, whether or not burning is required to meet that objective, the fuel treatment necessary to achieve successful burning, and the time of year burning should occur.
burning rate Wildland Fire Investigation Subcommittee WFISC Approved Rate at which a propellant and other combustibles burn.
burning rotation Fire Use Subcommittee FUSC Approved The planned number of years between prescribed fires on a specified area.
burning torch Equipment Technology Committee ETC Approved A flame generating device (e.g., a fount containing diesel oil or kerosene and a wick, or a backpack pump serving a flame-jet).
burnover Risk Management Committee RMC Approved An event in which a fire moves through a location or overtakes personnel or equipment where there is no opportunity to utilize escape routes and safety zones, often resulting in personal injury or equipment damage.
Buying Team Incident Business Committee IBC Approved A team that supports one or more incidents and is authorized to procure a wide range of services, supplies, and land and equipment rentals. In addition, the Buying Team Leader has the responsibility of coordinating property accountability with the Supply Unit Leader.
Buys Ballots Law Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, a law describing the relationship of the horizontal wind direction in the atmosphere to the pressure distribution; if one stands with the back to the wind, the pressure to the left is lower than to the right in the Northern Hemisphere.
cache Equipment Technology Committee ETC Approved A pre-determined complement of tools, equipment and/or supplies stored in a designated location, available for incident use.
calculated acres FRSC Fire Reporting Subcommittee In Development A measure of acres calculated (i.e., infrared) from a geospatial perimeter of a fire. More specifically, the number of acres within the current perimeter of a specific, individual incident, including unburned and unburnable islands.
calculation of probabilities Fire Behavior Subcommittee FBSC Approved Evaluation of all factors pertinent to probable future behavior of a going fire and of the potential ability of available forces to perform fire suppression operations on a specified time schedule.
calibrated airspeed National Interagency Aviation Committee NIAC Approved Indicated airspeed of an aircraft, corrected for position and instrument error. Equal to true airspeed in standard atmosphere at sea level.
Call When Needed (CWN) IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Employing office is a government or contractor entity There is no set work schedule; the person is in a “call-when-needed” status. Employee receives compensation for work
camp National Incident Management System Integration Committee NIMSIC Approved A geographical site within the general incident area (separate from the Incident Base) that is equipped and staffed to provide sleeping, food, water, and sanitary services to incident personnel.
campfire Communication, Education, and Prevention Committee CEPC In Development
candling Fire Behavior Subcommittee FBSC Approved The burning of the foliage of a single tree or a small group of trees, from the bottom up.
canopy Fire Environment Committee FENC Approved The stratum containing the crowns of the tallest vegetation present (living or dead), usually above 20 feet.
capability National Coordination System Committee NCSC In Development The extent of someone's or something's ability to support a wildland fire.
Carbon Dioxide (CO2) Risk Management Committee RMC Approved A colorless, odorless, nonpoisonous gas, which results from fuel combustion and is normally a part of the ambient air.
Carbon Monoxide (CO) Risk Management Committee RMC Approved A colorless, odorless, poisonous gas produced by incomplete fuel combustion.
carcinogen Risk Management Committee RMC Approved Any substance that can cause or contribute to the production of cancer.
cardinal altitudes National Interagency Aviation Committee NIAC Approved Odd or "even" thousand-foot (305 m) altitudes or flight levels. E.g., 5,000, 6,000, 7,000; FL 250, FL 260, and FL 270.
cardinal directions National Interagency Aviation Committee NIAC Approved North, south, east, west; used for giving directions and information from the ground or air in describing the fire (e.g., the west flank or east flank, not right flank or left flank).
career IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Employing office is a government entity Employees are permanent employees Year-round work schedule Employee receives compensation for work
career-seasonal IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Employing office is a government entity Employees are permanent employees who are placed in nonduty/nonpay status and recalled to duty in accordance with pre-established conditions of employment Annually recurring periods of work of at least 6 months, but less than 12 months, during a calendar year Employee receives compensation for work
cargo chute Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A parachute designed and rigged for dropping equipment and supplies from an aircraft.
cargo compartment National Interagency Aviation Committee NIAC Approved An internal area of an aircraft specifically designed to carry baggage or cargo.
cargo drop National Interagency Aviation Committee NIAC Approved Dropping of equipment or supplies, with or without a parachute, from an aircraft in flight.
cargo hook Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Mechanically and electrically operated hook attached to the bottom of a helicopter to which a sling load is attached.
cargo net Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Net attached to the cargo hook of a helicopter, used to carry cargo.
cargo rack Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Externally mounted rack for transporting supplies or cargo aboard a helicopter.
carousel hook Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A remote hook attached to the end of a longline. It has four or more individual hooks which can be independently released, allowing the pilot to fly cargo loads to different locations without landing.
carried wet IOSC Incident Operations Subcommittee Archived Booster hose carried full of water during mild weather to speed discharge of water on fire without filling or priming from tank.
carrier fuels Fire Use Subcommittee FUSC Approved The fuels that support the flaming front of the moving fire.
casual employee or hire Incident Business Committee IBC Approved A person hired and compensated under the Pay Plan for Emergency Workers.
casual hire IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Term of appointment is based on duration of the emergency situation for which the employee is hired. Employee receives compensation for work based on Administratively Determined (AD) Pay Plan for Emergency Workers
category day Smoke Committee SmoC Approved A numerical index related to the ability of the atmosphere to disperse smoke. Different agencies use different scales [e.g., in South Carolina, the current scale is based on ventilation factor and ranges from 1 (poor) to 5 (excellent)].
catface IOSC Incident Operations Subcommittee, Wildland Fire Investigation Subcommittee WFISC, Hazard Tree and Felling Subcommittee HTTFS Approved Defect on the surface of a tree resulting from a wound where healing has not re-established the normal cross-section.
ceiling Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, the height ascribed to the lowest layer of clouds or obscuring phenomena when it is reported as broken, overcast, or obscuration and not classified "thin" or "partial." The ceiling is termed unlimited when the foregoing conditions are not satisfied.
celsius Fire Weather Subcommittee FWS Approved According to the American Meteorological Society, same as centigrade temperature scale, by convention. Centigrade temperature scale is a temperature scale with the ice point of water at 0 degrees and the boiling point at 100 degrees.
center firing Fire Use Subcommittee FUSC Approved Method of broadcast burning in which fire is ignited in the center of the area to create a strong draft; additional fires are then ignited progressively nearer the outer control lines (sometimes in one step) as indraft increases so as to draw the flames and smoke toward the center. 
center location National Coordination System Committee NCSC Approved The city and state pairing for the dispatch center location
centrifugal pump Equipment Technology Committee ETC Approved Pump which expels water by centrifugal force through the ports of a circular impeller rotating at high speed. With this type of pump, the discharge line may be shut off while the pump is running without damaging the pump or hose.
ceremonial fire Communication, Education, and Prevention Committee CEPC In Development
certifying official Incident and Position Standards Committee IPSC Approved The agency official at the home unit who is responsible for authorizing and granting position certification per agency policy. The agency official is responsible for completing the agency certification block located on the inside front cover of a Position Task Book. 
chain IOSC Incident Operations Subcommittee Approved Unit of measure in land survey, equal to 66 feet (20 M) (80 chains equal 1 mile). Commonly used to report fire perimeters and other fireline distances, this unit is popular in fire management because of its convenience in calculating acreage (e.g., 10 square chains equal one acre).
chain lightning Fire Weather Subcommittee FWS Approved Lightning in a long zigzag or apparently broken line.
chain of command IOSC Incident Operations Subcommittee, National Incident Management System Integration Committee NIMSIC Approved The orderly line of authority within the rank of incident management organizations.
chainsaw/brush saw/weed trimmer Communication, Education, and Prevention Committee CEPC In Development A powered garden, agricultural, and/or forestry tool used to trim weeds, small trees and other foliage.
char (byproduct) Wildland Fire Investigation Subcommittee WFISC Approved Carbonaceous material formed by incomplete combustion of an organic material, most commonly wood; remains of burned materials.
char (fire simulation) Wildland Fire Investigation Subcommittee WFISC Approved In fire simulation, a darkened area within the fire perimeter; usually indicates fire has already passed through; usually created by an opaque material blocking out a selected portion of basic scene illumination.
char height Fire Use Subcommittee FUSC Approved The vertical distance above ground scorched or blackened on a tree bole.
charged line Equipment Technology Committee ETC Approved Hose filled with water under pressure and ready to use.
chase truck Equipment Technology Committee ETC Approved Vehicle that carries crew gear, supplies, and operational equipment for initial/extended attack.
check line IOSC Incident Operations Subcommittee Approved A temporary fireline constructed at right angles to the control line and used to hold a backfire in check as a means of regulating the heat or intensity of the backfire.
check valve Equipment Technology Committee ETC Approved A valve that permits flow of liquid through a hose or pipe in one direction but prevents a return flow. Uses include the prevention of backflow on uphill hose lays, loss of prime with centrifugal pumps and chemical contamination in fire chemical mixing systems. 
check-in National Incident Management System Integration Committee NIMSIC Approved The process whereby resources first report to an incident. Check-in locations include incident command post (ICP), base or camps, staging areas, helibases, or direct to a tactical assignment. All responders, regardless of agency affiliation, report in to receive an assignment.
chevron burn Fire Use Subcommittee FUSC Approved Burning technique in which lines of fire are started simultaneously from the apex of a ridge point, and progress downhill, maintaining position along the contour; used in hilly areas to ignite ridge points or ridge ends.
Chief National Incident Management System Integration Committee NIMSIC Approved The ICS title for individuals responsible for the management of functional sections: Operations, Planning, Logistics, and Finance/Administration.
chief of party Incident Business Committee IBC Approved The chief of party is responsible to the sending unit dispatcher until destination is reached. Chief of party is responsible for all traveling personnel assigned on the manifest list.
child (0-12) Communication, Education, and Prevention Committee CEPC In Development
cigar/cigarette/pipe Communication, Education, and Prevention Committee CEPC In Development
circumstantial evidence Wildland Fire Investigation Subcommittee WFISC Approved Testimony or information not based on actual personal knowledge or observation, but dependent on inference of other facts or experience. For example, testimony that defendant's cigarette lighter was found in ashes of a fire.
cirrus Fire Weather Subcommittee FWS Approved A form of high cloud, composed of ice crystals, which seldom obscures the sun.
claim Incident Business Committee IBC Approved A written demand for a specific amount of money or other objects of value, other than ordinary obligations incurred for services, supplies, or things.
claimant Incident Business Committee IBC Approved An individual, partnership, association, corporation, country, the federal government, state, or other political subdivision asserting a right, demand, or claim against another entity.
Class A foam Equipment Technology Committee ETC Approved Foam intended for use on Class A or woody fuels; made from hydrocarbon-based surfactant, therefore lacking the strong filming properties of Class B foam, but possessing excellent wetting properties.
Class B foam Equipment Technology Committee ETC Approved Foam designed for use on Class B or flammable liquid fires; made from fluorocarbon-based surfactants, therefore capable of strong filming action, but incapable of efficient wetting of Class A fuels.
Class I Areas (air quality) Fire Use Subcommittee FUSC Approved Geographic areas designed by the Clean Air Act subject to the most stringent restrictions on allowable increment of air quality deterioration. Class I areas include Forest Service wildernesses and nation memorial parks over 5,000 acres, National Parks exceeding 6,000 acres, international parks, as well as other designated lands. 
Class II Areas (air quality) Fire Use Subcommittee FUSC Approved All areas of the country not designated Class I, including everything from non-Class I areas to urban areas. A greater amount of air pollution can be added to these areas than Class I.
classroom training (event) National Coordination System Committee NCSC Approved An event dealing with a scheduled activity in a classroom setting or other controlled environment that provides instruction so as to make attendees fit or qualified for incident support activities.
Clean Air Act Risk Management Committee RMC, Fire Use Subcommittee FUSC Approved A federal law enacted to ensure that air quality standards are attained and maintained. Initially passed by Congress in 1963, it has been amended several times.
clear text National Incident Management System Integration Committee NIMSIC Approved Communication that does not use codes.
climate Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved The prevalent or characteristic meteorological conditions of any place or region, and their extremes.
climate class FDSC Fire Danger Subcommittee Approved In NFDRS, one of four classifications of general climate of an area.
climatological breakpoint FDSC Fire Danger Subcommittee Approved Points on the cumulative distribution of one fire weather/fire danger index without regard to associated fire occurrence/business.
clock method National Interagency Aviation Committee NIAC Approved Means of establishing a flight path to a target on a fire by referring to clock directions from the aircraft's present location, with the nose of the aircraft pointing at 12:00.
closed area Fire Use Subcommittee FUSC Approved An area in which specified activities or entry are temporarily restricted to reduce risk of human-caused fires or to mitigate the risk to human health or safety by potential or on-going wildland fires.
closure Communication, Education, and Prevention Committee CEPC, Fire Use Subcommittee FUSC Approved An administrative action limiting or prohibiting access to a specific geographic or jurisdictional area for the purposes of reducing wildfire or the risk it poses to life, property, and/or resources. Example of use: "Pursuant to 36 C.F.R. 261.50 (a) and (b), it is hereby ordered that the prohibitions hereinafter set forth apply to the general forest area of the Ozark-St. Francis National Forests until further notice."
cloud Fire Weather Subcommittee FWS Approved A visible cluster of minute water/ice particles in the atmosphere.
cloudy Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved Adjective class representing the degree to which the sky is obscured by clouds. In weather forecast terminology, expected cloud cover of about 0.7 or more warrants use of this term. In the National Fire Danger Rating System, 0.6 or more cloud cover is termed "cloudy."
co-op fire Incident Business Committee IBC Approved Refers to federal, state, and local cooperative fire programs.
cold front Fire Weather Subcommittee FWS Approved The leading edge of a relatively cold air mass which displaces warmer air, causing it to rise. If the lifted air contains enough moisture, cloudiness, precipitation and even thunderstorms may result. As fronts move through a region, in the Northern Hemisphere, the winds at a given location will experience a marked shift in direction. Ahead of an approaching cold front, winds will usually shift gradually from southeast to south, and on to southwest. As a cold front passes, winds shift rapidly to west, then northwest. Typical cold front windspeeds range between 15 and 30 mph but can be much higher. 
cold line IOSC Incident Operations Subcommittee Approved Fireline that has been controlled. The fire has been mopped up for a safe distance inside the line and can be considered safe to leave unattended.
cold trailing IOSC Incident Operations Subcommittee Approved A method of controlling a partly dead fire edge by carefully inspecting and feeling with the hand for heat to detect any fire, digging out every live spot, and trenching any live edge.
collective control National Interagency Aviation Committee NIAC Approved Controls the pitch angle of the main (helicopter) rotor blades. Used as primary altitude control.
colonizer Fire Use Subcommittee FUSC Approved Species of vegetation that establish on a burned (or otherwise denuded) site from seed.
combination nozzle Equipment Technology Committee ETC Approved A nozzle is designed to provide either a solid stream or a fixed spray pattern suitable for applying water, wet water or foam solution.
combination nozzle tip Equipment Technology Committee ETC Approved Two attached straight stream nozzle tips of different orifice size used to increase or restrict water flow.
combustion Fire Weather Subcommittee FWS Approved The rapid oxidation of fuel in which heat and usually flame are produced. Combustion can be divided into four phases: preignition, flaming, smoldering, and glowing.
combustion efficiency Fire Weather Subcommittee FWS Approved The relative amount of time a fire burns in the flaming phase of combustion, as compared to smoldering combustion. A ratio of the amount of fuel that is consumed in flaming combustion compared to the amount of fuel consumed during the smoldering phase, in which more of the fuel material is emitted as smoke particles because it is not turned into carbon dioxide and water. 
combustion period Fire Weather Subcommittee FWS Approved Total time required for a specified fuel component to be completely consumed.
combustion rate Fire Weather Subcommittee FWS Approved Rate of heat release per unit of burning area per unit of time.
command National Incident Management System Integration Committee NIMSIC Approved The act of directing, ordering, or controlling by virtue of explicit statutory, regulatory, or delegated authority.
command climate Leadership Committee LC Approved The working environment within the influence of a particular leader or chain of command. The command climate is based on the subordinates' understanding of how they are expected to perform, how they are treated, and how they must conform to the leader's style. 
command presence Leadership Committee LC Approved How leaders present themselves to others. The personal attributes and traits that determine whether leaders are worthy of trust and respect from their subordinates.
Command Staff National Incident Management System Integration Committee NIMSIC Approved A group of incident personnel that the Incident Commander or Unified Command assigns to support the command function at an ICP. Command staff often include a PIO, a Safety Officer, and a Liaison Officer, who have assistants as necessary. Additional positions may be needed, depending on the incident.
comments (feature class) Geospatial Subcommittee GSC Approved Additional information describing the feature.
comments (repair) Approved Comments on the suppression repair for each feature.
commercial transport vehicle Communication, Education, and Prevention Committee CEPC In Development A vehicle required to be registered which is used or maintained for the transportaiton of persons for hire, compensation, or profit or designed, used or maintained primarily for the transportation of property.
Communications Unit National Incident Management System Integration Committee NIMSIC Approved Communications Unit staff install and test communications equipment, supervise and operate the incident communications center, distribute and recover communications equipment assigned to incident personnel, and maintain and repair communications equipment on site.Most complex incidents have an incident Communications Plan. Staff in the Communications Unit produce this plan, as they are responsible for assigning radio frequencies; establishing voice and data networks for command, tactical, support, and air units; setting up on-scene telephoneand public-address equipment; and providing any necessary off-incident communication links.
community event (event) National Coordination System Committee NCSC Approved An event initiated by local private or government organizations that require non-emergency services for a general gathering such as a concert, convention, or parade.
Community Wildfire Protection Plan (CWPP) WMSC WUI Mitigation Subcommittee, Communication, Education, and Prevention Committee CEPC Approved A plan developed in the collaborative framework established by the Wildland Fire Leadership Council and agreed to by state, Tribal, and local government, local fire department, other stakeholders and federal land management agencies managing land in the vicinity of the planning area. A Community Wildfire Protection Plan (CWPP) identifies and prioritizes areas for hazardous fuel reduction treatments and recommends the types and methods of treatment on Federal and non-Federal land that will protect one or more at-risk communities and essential infrastructure and recommends measures to reduce structural ignitability throughout the at-risk community. A CWPP may address issues such as wildfire response, hazard mitigation, community preparedness, or structure protection - or all of the above. 
compact Incident Business Committee IBC Approved A formal working agreement among agencies to obtain mutual aid.
compactness Fire Use Subcommittee FUSC Approved Spacing between fuel particles.
company IOSC Incident Operations Subcommittee Archived Any piece of (fire) equipment having a full complement of personnel.
compare and contrast (fire damage) Wildland Fire Investigation Subcommittee WFISC Approved The practice of comparing and contrasting the fire damage on different surfaces of an object that has been subjected to the oncoming fire.
compare and contrast (investigation) Wildland Fire Investigation Subcommittee WFISC Approved An investigative technique that involves comparing same sized indicators within an indicator category at separate locations; looking for either differences or similarities in appearance.
compass Incident and Position Standards Committee IPSC Approved An instrument used for showing direction, consisting of a magnetic needle swinging freely on a pivot and pointing to magnetic north.
compass rose IOSC Incident Operations Subcommittee Archived A circle, graduated in degrees, printed on some charts or marked on the ground at an airport or heliport. It is used as a reference to either true or magnetic direction.
Compensation-for-Injury Manager Incident Business Committee IBC Archived Person responsible to the Compensation/Claims Unit Leader for administrative matters arising from serious injuries and fatalities occurring on the incident.
Compensation/Claims Unit National Incident Management System Integration Committee NIMSIC, Incident Business Committee IBC Approved Compensation and Claims Unit staff are responsible for financial concerns resulting from property damage, injuries, or fatalities at the incident. The specific activities vary depending on the incident. Staff handling injury compensation ensure that all forms needed by workers’ compensation programs and local agencies are completed. These staff also typically maintain files on injuries and illnesses associated with the incident and obtain written witness statements. Since Medical Unit staff may also perform some of these tasks, the Medical and the Compensation and Claims Units should coordinate closely. The Compensation and Claims Unit staff may assist with civil tort claims investigations involving incident property, and the staff maintain logs on the claims, obtain witness statements, and document investigations and agency follow-up activities.
competency Incident and Position Standards Committee IPSC Approved A broad description that groups core behaviors necessary to perform a specific function.
competent ignition source Wildland Fire Investigation Subcommittee WFISC Approved Any item which can produce sufficient heat over a sufficient duration of time capable of bringing forest fuels to their ignition temperature and sustain open flame combustion.
complex identifier FRSC Fire Reporting Subcommittee Approved The Globally Unique Identifier (GUID) of the complex.
complex name FRSC Fire Reporting Subcommittee Approved The name of the complex that the fire is assigned.
Compressed Air Foam Systems (CAFS) Equipment Technology Committee ETC Approved A generic term used to describe foam systems consisting of an air compressor (or air source), a water pump, and foam solution.
computed gross weight National Interagency Aviation Committee NIAC Approved Term used in calculating from performance charts the permissible helicopter payload at which a helicopter is capable of hovering in ground effect or hovering out of ground effect, based on pressure altitude and air temperature.
concentrate Equipment Technology Committee ETC Approved A substance that has been concentrated; specifically, a liquid that has been made denser, as by the removal of some of its water.
conceptual model Fire Weather Subcommittee FWS Approved A model that is a diagram or description of a set of relationships between factors that describe how a system works, such as an ecological model.
condensation Fire Weather Subcommittee FWS Approved The process by which a gas becomes a liquid.
condition class Fire Use Subcommittee FUSC Approved Depiction of the degree of departure from historical fire regimes, possibly resulting in alterations of key ecosystem components. These classes categorize and describe vegetation composition and structure conditions that currently exist inside the Fire Regime Groups. Based on the coarse-scale national data, they serve as generalized wildfire rankings. The risk of loss of key ecosystem components from wildfires increases from Condition Class 1 (lowest risk) to Condition Class 3 (highest risk).
condition of vegetation FDSC Fire Danger Subcommittee Approved Stage of growth or degree of flammability of vegetation that forms part of a fuel complex. Herbaceous stage is at times used when referring to herbaceous vegetation alone. In grass areas minimum qualitative distinctions for stages of annual growth are usually green, curing, and dry or cured. 
conduction Fire Weather Subcommittee FWS Approved Heat transfer through a material from a region of higher temperature to a region of lower temperature.
confine IOSC Incident Operations Subcommittee Approved A wildfire response strategy of restricting a wildfire to a defined area, primarily using natural barriers that are expected to restrict the spread of the wildfire under the prevailing and forecasted weather conditions.
confinement Fire Use Subcommittee FUSC Approved The strategy employed in appropriate management responses where a fire perimeter is managed by a combination of direct and indirect actions and use of natural topographic features, fuel, and weather factors.
conflagration Fire Weather Subcommittee FWS Approved A raging, destructive fire. Often used to connote such a fire with a moving front as distinguished from a fire storm.
conflagration threat Fire Weather Subcommittee FWS Approved Likelihood that a wildfire capable of causing considerable damage will occur.
consistency (foam) Equipment Technology Committee ETC Approved Uniformity and size of bubbles.
constant danger FDSC Fire Danger Subcommittee Approved Resultant of all fire danger factors that are relatively unchanging in a specific area (e.g., resource values at risk, topography, fuel type, exposure to prevailing wind).
consumption Fire Use Subcommittee FUSC Approved The amount of a specified fuel type or strata that is removed through the fire process, often expressed as a percentage of the preburn weight.
contact email (data creation) Data Management Committee DMC Approved Email of the incident-based contact responsible for data creation.
contact name (data creation) Data Management Committee DMC Approved Name of the incident-based contact responsible for data creation.
contact phone (data creation) Data Management Committee DMC Approved Phone number for the incident-based contact responsible for data creation.
contact phone (dispatch center) Approved Phone number for the Dispatch Center.
contained IOSC Incident Operations Subcommittee Approved The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire's spread.
containment (hazardous materials) Fire Use Subcommittee FUSC Approved The act of controlling hazardous spilled or leaking materials.
containment (wildfire) Fire Use Subcommittee FUSC Approved The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire's spread.
continental climate Fire Weather Subcommittee FWS Approved Climate that is characteristic of the interior of a land mass of continental size, marked by large annual diurnal and day-to-day ranges of temperature, low relative humidity and irregular precipitation.
contingency actions IOSC Incident Operations Subcommittee, wfnwcgorg:ICSC Approved A back-up plan of action when actions described in the primary plan are no longer appropriate. Contingency actions are required to be taken when the result exceeds its intent. Actions are taken to return the project to its intended design.
contingency plan Fire Use Subcommittee FUSC Approved The portion of a prescribed fire plan, incident action plan, or implementation plan that identifies possible but unlikely events and the contingency resources needed to mitigate those events.
contingency resources Fire Use Subcommittee FUSC Approved Planned and identified fire suppression personnel and equipment that mitigate possible but unlikely events that exceed or are expected to exceed holding resource capabilities.
contour line Incident and Position Standards Committee IPSC Approved A line on a map or chart indicating elevation in feet, and connects all points of the same height above sea level.
contour map IOSC Incident Operations Subcommittee Archived A map having lines of equal elevation that represent the land surface (Topographic).
contract Incident Business Committee IBC Approved Any written agreement giving one party a right, a service, or a commodity in exchange for a right, a service, or a commodity. Contracts include land use permits, purchase orders, equipment rental agreements, leases, etc.
contracted resource vendor National Coordination System Committee NCSC Approved The name of the company who, through a contract, provides resources to support incident management activities.
Contracting Officer (CO) Incident Business Committee IBC Approved Agency personnel with specific delegation of procurement authority.
Contracting Officer’s Technical Representative (COTR) Incident Business Committee IBC Approved An individual designated by the Contracting Officer to provide technical support for the contract within specific authority and limitations as specified in the delegation. The COTR/COR must be agency certified.
contractor Incident Business Committee IBC Approved Private sector personnel, vendor or business contracted to provide goods and services to a government agency.
control force Fire Use Subcommittee FUSC Approved Personnel and equipment used to control a fire.
control line Fire Use Subcommittee FUSC Approved An inclusive term for all constructed or natural barriers and treated fire edges used to control a fire.
control time IOSC Incident Operations Subcommittee Approved The time a fire is declared controlled.
controlled Fire Use Subcommittee FUSC Approved The completion of control line around a fire, any spot fires therefrom, and any interior islands to be saved; burned out any unburned area adjacent to the fire side of the control lines; and cool down all hotspots that are immediate threats to the control line, until the lines can reasonably be expected to hold under the foreseeable conditions. 
controlled airspace National Interagency Aviation Committee NIAC Approved Airspace of defined dimensions within which air traffic control service is provided to IFR (Instrument Flight Rules) and VFR (Visual Flight Rules) flights in accordance with the airspace classification.
controlling nozzle Equipment Technology Committee ETC Approved Shut-off nozzle that permits the nozzle operator to open or close the nozzle or adjust the pattern of the stream.
convection (energy transfer) Fire Weather Subcommittee FWS Approved The transfer of heat by the movement of a gas or liquid; convection, conduction, and radiation are the principal means of energy transfer.
convection (meteorology) Fire Weather Subcommittee FWS Approved As specialized in meteorology, atmospheric motions that are predominantly vertical in the absence of wind (which distinguishes this process from advection), resulting in vertical transport and mixing of atmospheric properties.
convection column Fire Behavior Subcommittee FBSC, Fire Weather Subcommittee FWS Approved The rising column of gases, smoke, fly ash, particulates, and other debris produced by a fire. The column has a strong vertical component indicating that buoyant forces override the ambient surface wind.
convective activity Fire Weather Subcommittee FWS Approved General term for manifestations of convection in the atmosphere, alluding particularly to the development of convective clouds and resulting weather phenomena, such as showers, thunderstorms, squalls, hail, tornadoes, etc.
convective-lift fire phase Fire Behavior Subcommittee FBSC Approved The phase of a fire when most of the emissions are entrained into a definite convection column.
convergence Fire Weather Subcommittee FWS Approved The term for horizontal air currents merging together or approaching a single point, such as at the center of a low pressure area producing a net inflow of air. When this occurs in the lower atmosphere, the excess air is removed by rising air currents. Expansion of the rising air above a convergence zone results in cooling, which in turn often gives condensation (clouds) and sometimes precipitation. 
convergence zone (fire weather) Fire Weather Subcommittee FWS Approved In fire weather, that area where two winds come together from opposite directions and are forced upwards often creating clouds and precipitation.
convergence zone (fire) Fire Weather Subcommittee FWS Approved The area of increased flame height and fire intensity produced when two or more fire fronts burn together.
conversion burning Fire Use Subcommittee FUSC Approved Burning an area where brush has excluded forest reproduction to prepare the area for tree planting.
cooperating agency National Incident Management System Integration Committee NIMSIC Approved An agency supplying assistance other than direct operational or support functions or resources to the incident management effort. (e.g. Red Cross, law enforcement agency, telephone company, etc).
cooperator wfnwcgorg:ICSC Approved A federal, Tribal, state, or local agency that participates with another agency(s) in planning and conducting fire or emergency management projects and activities.
coordinates IOSC Incident Operations Subcommittee Archived The intersection of lines of reference, usually expressed in degrees/minutes/seconds of latitude and longitude, used to determine or report position or location.
coordination Incident Business Committee IBC Approved The process of systematically analyzing a situation, developing relevant information, and informing appropriate command authority of viable alternatives for selection of the most effective combination of available resources to meet specific objectives. The coordination process (which can be either intra- or interagency) does not involve dispatch actions. However, personnel responsible for coordination may perform command or dispatch functions within limits established by specific agency delegations, procedures, legal authority, etc. 
coordination center National Coordination System Committee NCSC, Incident Business Committee IBC Approved Term used to describe any facility that is used for the coordination of agency or jurisdictional resources in support of one or more incidents.
Coriolis Force Fire Weather Subcommittee FWS Approved An apparent force due to the rotation of the earth that causes a deflection of air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This force maximizes at the poles and is essentially zero at the equator.
corrosion Equipment Technology Committee ETC Approved Result of chemical reaction between a metal and its environment (i.e., air, water, and impurities in same).
cost Incident Business Committee IBC Approved The dollar amount associated with an incident.
cost sharing agreements Incident Business Committee IBC Approved Agreements that document the financial responsibility for incident resource costs, possibly identifying requirements of other party payments.
Cost Unit National Incident Management System Integration Committee NIMSIC, Incident Business Committee IBC Approved Cost Unit staff track costs, analyze cost data, make estimates, and recommend cost-saving measures. They ensure that equipment and personnel for which payment is expected are properly identified, obtain and record cost data, and analyze and prepare estimates of incident costs. Cost Unit staff provide cost estimates for resource use to Planning Section staff. The Cost Unit staff maintain information on the actual costs of all assigned resources.
council tool Equipment Technology Committee ETC Approved Long-handled combination rake and cutting tool, the blade of which is constructed of a single row of three or four sharpened teeth.
counter fire (emergency firing) IOSC Incident Operations Subcommittee Approved Emergency firing to stop, delay, or split a fire front, or to steer a fire.
counter fire (hasten spread) IOSC Incident Operations Subcommittee Approved Fire set between main fire and backfire to hasten spread of backfire.
country Data Management Committee DMC Approved A nation with its own government, occupying a particular territory.
country code Data Management Committee DMC Approved Short alphanumeric identification code for countries and dependent areas.
country subdivision Data Management Committee DMC Proposed New Political subdivisions that fall within a country
country subdivision code Data Management Committee DMC Approved A code for the identification of first-level administartive subdivisions within a country.
county code (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved The County Code identifying the county or equivalent entity at point of origin designated at the time of collection. Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
coupling Equipment Technology Committee ETC Approved Device that connects the ends of adjacent hoses or other components of hose.
course National Interagency Aviation Committee NIAC Approved In aviation, the intended direction of horizontal flight.
cover Fire Use Subcommittee FUSC Approved The area on the ground covered by the combined aerial parts of plants expressed as a percent of the total area.
cover type Fire Use Subcommittee FUSC Approved The designation of a vegetation complex described by dominant species, age, and form.
coverage level Equipment Technology Committee ETC Approved Recommended amount of aerially applied retardant keyed to the NFDRS fuel models and/or fire behavior models. Coverage level 2 represents 2 gallons of retardant per hundred square feet. Levels range from 1 to 6 for most fuel models. A coverage level of greater than 6 is for heavy fuels. The levels can be adjusted for fire behavior. 
coyote tactics IOSC Incident Operations Subcommittee Approved A progressive line construction duty involving self-sufficient crews which build fire line until the end of the operational period, remain at or near the point while off duty, and begin building fireline the next operational period where they left off.
crazing Wildland Fire Investigation Subcommittee WFISC Approved Fine cracking of glass, usually from heat of fire.
create date Geospatial Subcommittee GSC Approved Date the feature was created.
create name (feature class) Geospatial Subcommittee GSC Approved Name of the person creating the feature.
created by system Data Management Committee DMC Approved System that created the data record.
created on date time Data Management Committee DMC Approved Date and time the event record was created
creeping fire Fire Use Subcommittee FUSC Approved Fire burning with a low flame and spreading slowly.
crew IOSC Incident Operations Subcommittee Approved An organized group of firefighters under the leadership of a crew boss or other designated official.
crew shuttle IOSC Incident Operations Subcommittee Approved Transportation of fireline personnel to and/or from assigned fireline locations.
crew transport Equipment Technology Committee ETC Approved Any vehicle capable of transporting a specified number of personnel in a specified manner.
crisis communication coaches Risk Management Committee RMC Approved Agency employees who have actual experience dealing with a critical incident and are qualified as incident information officers.
criteria pollutants Fire Use Subcommittee FUSC Approved Pollutants deemed most harmful to public health and welfare and that can be monitored effectively. They include carbon monoxide (CO), lead (Pb), nitrogen oxides (Nox), sulfur dioxide (SO2), ozone (O3), particulate matter (PM) of aerodynamic diameter less than or equal to 10 micrometers (PM10) and particulate matter of aerodynamic diameter less than or equal to 2.5 micrometers (PM2.5). 
critical burnout time Fire Behavior Subcommittee FBSC Approved Total time a fuel can burn and continue to feed energy to the base of a forward-traveling convection column.
critical incident Risk Management Committee RMC Approved A fatality or other event that can have serious long-term adverse effects on the agency, its employees and their families, or the community.
Critical Incident Stress Debriefing (CISD) Risk Management Committee RMC Approved The process in which teams of professional and peer counselors provide emotional and psychological support to incident personnel who are or have been involved in a critical (highly stressful) incident.
Critical Incident Stress Management (CISM)/Peer Support (event) National Coordination System Committee NCSC Approved An event dealing with a critical incident event. Critical Incident Stress Management (CISM)/Peer Support is the selection and implementation of the most appropriate crisis intervention tactics to best respond to the needs of the situation. CISM has multiple components other than responding after a critical incident occurs. These components can be used before, during, and after a crisis. They include a wide range of various activities, including PreIncident Education (PIE), which provides for resiliency, planning and preparedness, acute crisis management, and post-incident follow up.
Critical Incident Stress Managment (CISM) (process) Risk Management Committee RMC Approved An adaptive short-term helping process that focuses solely on an immediate and identifiable problem to enable the individual(s) affected to return to their daily routine(s) more quickly and with a lessened likelihood of experiencing post-traumatic stress disorder.
cross shot IOSC Incident Operations Subcommittee Approved Intersecting lines of sight from two points to the same object, frequently used to determine location of a fire from lookouts.
crown consumption Fire Use Subcommittee FUSC Approved Combustion of the twigs, and needles or leaves of a tree during a fire.
crown cover Fire Use Subcommittee FUSC Approved The ground area covered by the crown of a tree as delimited by the vertical projection of its outermost perimeter.
crown fire Fire Weather Subcommittee FWS Approved A fire that advances from top to top of trees or shrubs more or less independent of a surface fire. Crown fires are sometimes classed as running or dependent to distinguish the degree of independence from the surface fire.
Crown Fraction Burned (CFB) Fire Behavior Subcommittee FBSC, Fire Environment Committee FENC Approved A theoretical concept that is used to model and classify crown fire. It may be observable after the fact in burn severity assessments.
crown out Fire Behavior Subcommittee FBSC Approved A fire that rises from ground into the tree crowns and advances from tree top to tree top. To intermittently ignite tree crowns as a surface fire advances.
crown ratio Fire Weather Subcommittee FWS Approved The ratio of live crown to tree height.
crown scorch Fire Use Subcommittee FUSC Approved Browning of needles or leaves in the crown of a tree or shrub caused by heating to lethal temperature during a fire. Crown scorch may not be apparent for several weeks after the fire.
crown scorch height Fire Use Subcommittee FUSC Approved The height above the surface of the ground to which a tree canopy is scorched.
crowning potential Fire Use Subcommittee FUSC Approved A probability that a crown fire may start, calculated from inputs of foliage moisture content and height of the lowest part of the tree crowns above the surface.
cumulonimbus Fire Weather Subcommittee FWS Approved The ultimate growth of a cumulus cloud into an anvil-shaped cloud with considerable vertical development, usually with fibrous ice crystal tops, and usually accompanied by lightning, thunder, hail, and strong winds.
cumulus Fire Weather Subcommittee FWS Approved A principal low cloud type in the form of individual cauliflower-like cells of sharp non-fibrous outline and less vertical development than cumulonimbus.
cup trench IOSC Incident Operations Subcommittee Approved A fireline trench on the downhill side of fire burning on steep slopes that is supposed to be built deep enough to catch rolling firebrands that could otherwise start fire below the fireline. A high berm on the outermost downhill side of the trench helps the cup trench catch material.
curb weight Equipment Technology Committee ETC Approved Weight of a truck empty (without payload and driver) but ready to drive, including a full fuel tank, cooling system, crankcase, tools, spare wheel, and all other equipment specified as standard.
cured FDSC Fire Danger Subcommittee Approved In the 1978 version of NFDRS, the herbaceous stage when herbaceous fuel moisture falls to 30% or less.
daily activity level FDSC Fire Danger Subcommittee Approved In fire danger rating, a subjective estimate of the degree of activity of a potential human-caused fire source relative to that which is normally experienced. Five activity levels are defined: none, low, normal, high, and extreme.
daily rate Incident Business Committee IBC Approved Paid on a calendar day basis (0001-2400).
damage differential Wildland Fire Investigation Subcommittee WFISC Approved The comparative differences of damage to objects resulting from the fire’s passage.
damage differential indicators Wildland Fire Investigation Subcommittee WFISC Approved The amount of fire related destruction to combustible objects determined by comparing opposing sides of an object.
data source (geospatial) Approved The database from which the polygon originated.
date Data Management Committee DMC Approved A particular day of a calendar year.
date current (geospatial data) Geospatial Subcommittee GSC Approved The last edit, update, of this GIS record.
date-time Data Management Committee DMC Approved The combination of date and time elements.
datum (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved The datum associated with the coordinates that identify the point of origin. Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
dead fuels Fire Behavior Subcommittee FBSC Approved Fuels with no living tissue in which moisture content is governed almost entirely by absorption or evaporation of atmospheric moisture (relative humidity and precipitation).
debris and open burning Communication, Education, and Prevention Committee CEPC In Development A fire spreading from any fire originally set for the purpose of clearing land or for rubbish, garbage, range, stubble, or meadow burning.
debris burning fire (prescribed) Fire Use Subcommittee FUSC Approved In prescribed fire terminology, a fire used to dispose of scattered, piled, or windrowed dead woody fuel, generally in the absence of a merchantable overstory. Its purpose is to reduce unsightly fuel concentrations, or consume unwanted natural fuels to facilitate subsequent resource management or land use actions on the area. 
debris burning fire (suppression) Fire Use Subcommittee FUSC Approved In fire suppression terminology, a fire spreading from any fire originally ignited to clear land or burn rubbish, garbage, crop stubble, or meadows (excluding incendiary fires).
debris/product fire (event) National Coordination System Committee NCSC Approved An event dealing with a fire spreading from any fire originally ignited to clear land or burn rubbish, garbage, crop stubble, or meadows (excluding incendiary fires).
deck Interagency Helicopter Operations Subcommittee IHOPS Approved The helibase operational area that includes the touchdown pad, safety circle, hover lanes, and external cargo transport area.
declination External Source The difference in degrees between true north and magnetic north.
deep-seated fire (structure) Fire Behavior Subcommittee FBSC Approved A fire that has gained headway and built up heat in a structure so as to require greater cooling for extinguishment.
deep-seated fire (wildland) Fire Behavior Subcommittee FBSC Approved A fire burning far below the surface in duff, mulch, peat, or other combustibles as contrasted with a surface fire.
deepening Fire Weather Subcommittee FWS Approved As it refers to atmospheric pressure, a decrease in the central pressure of a low. This is usually accompanied by intensification of the cyclonic circulation (counter-clockwise wind flow around the low).
deflagration (burning) Wildland Fire Investigation Subcommittee WFISC Approved A burning with great heat and intense light.
deflagration (decomposition) Wildland Fire Investigation Subcommittee WFISC Approved Chemical decomposition by burning material in which the reaction is less than sonic velocity, for example, low explosives.
defusing Risk Management Committee RMC Approved This is an informal session held immediately following the incident, within 24 hours. It is peer support led, and focuses on initial venting of feelings and stress education.
degradation FCSC Fire Chemical Subcommittee Approved In a discussion of fire retardant slurries, deterioration of viscosity.
degree Incident and Position Standards Committee IPSC Approved A unit of angular measurement equal to one-360th part of the circumference of a circle. The entire globe contains 360 degrees, each degree contains 60 minutes, and each minute contains 60 seconds.
Delayed Aerial Ignition Devices (DAID) Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Polystyrene balls, 1.25 inches in diameter, containing potassium permanganate. The balls are fed into a dispenser, generally mounted in a helicopter, where they are injected with a water-glycol solution and then drop through a chute leading out of the helicopter. The chemicals react thermally and ignite in 25-30 seconds. The space between ignition points on the ground is primarily a function of helicopter speed, gear ratio of the dispenser, and the number of chutes used (up to four). 
delegation of authority National Incident Management System Integration Committee NIMSIC Approved A statement provided to the incident commander by the agency administrator delegating authority and assigning responsibility. The delegation of authority can include objectives, priorities, expectations, constraints and other considerations or guidelines as needed.
delete this Geospatial Subcommittee GSC Approved An attribute flag to tell editors to remove a feature added in error.
demob en route Proposed New The resource is no longer assigned to an incident and travel has started, but the resource has not yet arrived home.
demobilization National Incident Management System Integration Committee NIMSIC Approved The orderly, safe, and efficient return of an incident resource to its original location and status.
Demobilization Unit National Incident Management System Integration Committee NIMSIC Approved Demobilization Unit staff develop an Incident Demobilization Plan that includes specific instructions for all personnel and other resources to be demobilized. They begin their work early in the incident, creating rosters of personnel and resources and obtaining any missing information as check-in proceeds. Once the Incident Commander or Unified Command has approved the Incident Demobilization Plan, Demobilization Unit staff ensure its distribution at the incident and elsewhere, as necessary. For major incidents, demobilization plans are dynamic and the staff in the Demobilization Unit may need to update them frequently.
dense layer Fire Weather Subcommittee FWS Approved A layer of clouds whose ratio of dense sky cover to total sky cover is more than one-half.
dense sky cover Fire Weather Subcommittee FWS Approved Sky cover that prevents detection of higher clouds or the sky above it.
density (foam) Equipment Technology Committee ETC Approved The ratio of the original volume of the nonaerated foam solution to the resultant volume of foam. The inverse of expansion.
Departure from Average Greenness (DA) FDSC Fire Danger Subcommittee Approved An NDVI-derived image of vegetation greenness compared to its average greenness for the current week of the year.
depression (topographic) Incident and Position Standards Committee IPSC Approved A low place in the ground having no outlet for surface drainage.
Depth of Burn (DOB) Fire Weather Subcommittee FWS Approved The reduction in forest floor thickness due to consumption by fire.
depth of char indicators Wildland Fire Investigation Subcommittee WFISC Approved Sometimes referred to as "alligatoring", where combustible material appears to have a fissured or scaly appearance similar to an alligator's hide. Most commonly associated with finished lumber products, such as boards and fence posts.
Deputy National Incident Management System Integration Committee NIMSIC Approved A fully qualified individual who, in the absence of a superior, can be delegated the authority to manage a functional operation or to perform a specific task. In some cases, a deputy can act as relief for a superior, and, therefore, should be fully qualified in the position. Deputies generally can be assigned to the Incident Commander, EOC director, General Staff, and branch directors.
derailment Communication, Education, and Prevention Committee CEPC In Development A type of train wreck that occurs when a rail vehicle such as a train comes off its rails.
desiccant Equipment Technology Committee ETC Approved Chemical that, when applied to a living plant, causes or accelerates drying of its aerial parts; used to facilitate burning of living vegetation by substantially lowering fuel moisture content within a few hours.
designated area Fire Use Subcommittee FUSC Approved Those areas identified as principal population centers or other areas requiring protection under state or federal air quality laws or regulations.
Designated Dispatch Point (DDP) Incident Business Committee IBC Approved The address where the unit must be physically located, and dispatched from, during the mandatory availability period.
detection method IOSC Incident Operations Subcommittee, FRSC Fire Reporting Subcommittee Approved The means by which the fire was initially observed.
detonation Wildland Fire Investigation Subcommittee WFISC Approved An extreme rapid decomposition of a material in which the reaction is more than a sonic velocity, for example, high explosives.
device Communication, Education, and Prevention Committee CEPC In Development
dew point Fire Weather Subcommittee FWS Approved Temperature to which a specified parcel of air must cool, at constant pressure and water-vapor content, in order for saturation to occur. The dew point is always lower than the wet-bulb temperature, which is always lower than the dry-bulb temperature, except when the air is saturated and all three values are equal. Fog may form when temperature drops to equal the dew point. 
diagram Wildland Fire Investigation Subcommittee WFISC Approved A scale drawing showing information about a fire scene.
die-out pattern indicators Wildland Fire Investigation Subcommittee WFISC Approved Fingers or islands of less intensely burned areas or areas where the fire has self extinguished.
digital elevation model Fire Weather Subcommittee FWS Approved A set of points which defines the terrain as numbers for computer applications. This data may be used to draw contours, make ortho photos, slope maps, and drive fire models.
dilution Fire Use Subcommittee FUSC Approved A control strategy used in managing smoke from prescribed fires in which smoke concentration is reduced by diluting it through a greater volume of air, either by scheduling during good dispersion conditions or burning at a slower rate.
dipsite (helicopter) National Interagency Aviation Committee NIAC Approved A natural or manmade water site that a helicopter can fill their bucket with water, such as a stream, river, lake, swimming pool, etc...
direct attack IOSC Incident Operations Subcommittee Approved Any treatment applied directly to burning fuel such as wetting, smothering, or chemically quenching the fire or by physically separating the burning from unburned fuel.
direct line IOSC Incident Operations Subcommittee Approved Any treatment applied directly to burning fuel such as wetting, smothering, or chemically quenching the fire or by physically separating the burning from unburned fuel.
direct protection area IOSC Incident Operations Subcommittee Approved That area for which a particular fire protection organization has the primary responsibility for attacking an uncontrolled fire and for directing the suppression action. Such responsibility may develop through law, contract, or personal interest of the firefighting agent (e.g., a lumber operator). Several agencies or entities may have some basic responsibilities (e.g., private owner) without being known as the fire organization having direct protection responsibility. 
directional vectors Wildland Fire Investigation Subcommittee WFISC Approved The physical characteristics of the indicators that show the direction of fire spread, i.e., advancing, backing, or lateral.
directions (driving) Approved Driving directions to water source for trucks.
Director National Incident Management System Integration Committee NIMSIC Approved The ICS title for individuals responsible for supervision of a branch. Also, an organizational title for an individual responsible for managing and directing the team in an EOC.
discovery Wildland Fire Investigation Subcommittee WFISC Approved Determination that a fire exists. Location and reporting of a fire is not required as is with detection.
discovery time IOSC Incident Operations Subcommittee Approved Elapsed time from start of fire (known or estimated) until the time of the first discovery that results directly in fire suppression action.
discrete frequency National Coordination System Committee NCSC Approved A separate radio frequency most commonly used in air traffic control which reduces frequency congestion by controlling the number of aircraft or other resources operating on a particular frequency.
dispatch National Coordination System Committee NCSC, National Incident Management System Integration Committee NIMSIC, Incident Business Committee IBC Approved The ordered movement of a resource or resources to an assigned operational mission, or an administrative move from one location to another.
dispatch center National Coordination System Committee NCSC, Incident Business Committee IBC Approved An organization from which resources are ordered, mobilized or assigned to an incident and/or demobilized. The center may process requests, coordinate response, or track resources and information under the delegation of its benefiting agency(s).
dispatch center (current) National Coordination System Committee NCSC Approved The dispatch center actively supporting an incident and the resources assigned or a resource who is temporarily transferred for official action i.e. details, temporary duty station, etc.
dispatch center (home) National Coordination System Committee NCSC Approved The dispatch center associated with a resource’s home unit. The Home Dispatch Center is responsible for initial mobilization and is the Center associated with the resource when an assignment is completed.
dispatch center (ordering) National Coordination System Committee NCSC, Incident Business Committee IBC Approved The current dispatch center for an incident.
dispatch center (sending) National Coordination System Committee NCSC, Incident Business Committee IBC Approved Either the home or current dispatch center for a resource.
dispatch center area National Coordination System Committee NCSC Approved Name of the Dispatch Area or Zone
dispatch center location National Coordination System Committee NCSC Approved The city and state of the dispatch center
dispatch center name National Coordination System Committee NCSC Approved Name of the dispatch center
dispatch center unit identifier National Coordination System Committee NCSC Approved Unit Identifier for the dispatch center
dispatch tier National Coordination System Committee NCSC Approved Levels of the wildland fire dispatch and coordination system
dispatch/coordination center (geographic) UIB Unit Identifier Board Approved An organizational unit responsible for managing the effective coordination, mobilization, and demobilization of emergency management resources for their respective organizational unit e.g., GACC.
dispatch/coordination center (local) UIB Unit Identifier Board Approved An organizational unit responsible for initial attack dispatching, coordination of communications, intelligence gathering and dissemination, and logistical support for local incidents and field operations for their respective organizational unit e.g., local dispatch or Command Center.
dispersion Fire Weather Subcommittee FWS Approved The decrease in concentration of airborne pollutants as they spread throughout an increasing volume of atmosphere.
display class FDSC Fire Danger Subcommittee Approved In WIMS, a one-digit number representing the number of decision points used to evaluate the magnitude of the Staffing Index.
display class breakpoints FDSC Fire Danger Subcommittee Approved In WIMS, the climatological breakpoints separating the highest staffing levels. Commonly these are the index values corresponding to the 90th and 97th or 80th and 95th percentiles for the staffing index.
Distance Learning (DL) Incident and Position Standards Committee IPSC Archived A concept of providing access to quality wildland fire education and training using appropriate instructional technology, delivered anywhere, anytime to prepare a fire management work force to safely achieve fire management objectives.
Distance Measuring Equipment (DME) National Interagency Aviation Committee NIAC Approved Aircraft navigational equipment that provides the slant range distance in miles (kilometers) from the aircraft to the VOR (VHF Omnidirectional Radio Range) station to which the DME is tuned, usually at or near an airport.
distress/signal fire Communication, Education, and Prevention Committee CEPC In Development fire light to serve as a beacon or signal by light or smoke
Distributed Incident Simulation Exercise (DISE) Incident and Position Standards Committee IPSC Archived An on-line mission rehearsal event providing an individual or team with an experiential learning environment utilizing the National Interagency Incident Management System to "game" a computer generated incident from multiple training locations.
disturbance Fire Weather Subcommittee FWS Approved A weather system usually associated with clouds, rain and/or wind.
ditch/fence line burning Communication, Education, and Prevention Committee CEPC In Development Burning of accumulated vegetation in a ditch or fence line.
diurnal Fire Weather Subcommittee FWS Approved Daily, especially pertaining to cyclic actions which are completed within 24 hours, and which recur every 24 hours, such as temperature, relative humidity and wind.
divergence Fire Weather Subcommittee FWS Approved The expansion or spreading out of a horizontal wind field. Generally associated with high pressure and light winds.
Division National Incident Management System Integration Committee NIMSIC Approved The organizational level having responsibility for operations within a defined geographic area. Divisions are established when the number of resources exceeds the manageable span of control of the Section Chief. See Group.
Documentation Unit National Incident Management System Integration Committee NIMSIC Approved Documentation Unit staff maintain incident files and data for legal, analytical, and historical purposes, including a complete record of the major steps taken to resolve the incident. They also provide duplication services for incident personnel; compile, reproduce, and distribute the IAP; and maintain the files and records that are developed as part of the IAP and planning function.
dormant season burning Fire Use Subcommittee FUSC Approved Prescribed burning early in the dry season before the leaves and undergrowth are completely dry or before the leaves are shed, as an insurance against more severe fire damage later on.
double arsonist Wildland Fire Investigation Subcommittee WFISC Approved An offender who sets two fires at one site, at the same time, in a single event.
double doughnut Equipment Technology Committee ETC Approved Two lengths of hose rolled side by side or a single length rolled into two small coils for convenient handling.
double female coupling Equipment Technology Committee ETC Approved A hose-coupling device having two female swivel couplings to permit joining two male hose nipples of the same size and thread type when lines are laid with couplings in opposite or reverse directions.
double jacket hose Equipment Technology Committee ETC Approved Fire hose having two cotton or other fiber jackets outside the rubber lining or tubing.
double male coupling Equipment Technology Committee ETC Approved A hose-coupling device having two male thread nipples for connecting hose and for connecting two female couplings of the same diameter.
double shift Incident Business Committee IBC Approved Equipment is staffed with 2 operators or crews (1 per shift) and must be ordered and documented on a resource order. (Reference OF-294 general clauses for payment information.) Regardless of hiring method, on-shift time for operated equipment will be recorded with clock hours on the appropriate document, e.g., equipment hired under a daily rate will be posted with start and stop time for daily work.
doughnut roll Equipment Technology Committee ETC Approved A 50 or 100-foot length of hose or a 50-foot length of hose rolled up for easy handling. There are various ways of forming the doughnut. A convenient one has both couplings close together with the male thread protected by the female coupling.
downloading National Interagency Aviation Committee NIAC Approved A calculated reduction in actual payload to provide a margin of safety.
dozer Equipment Technology Committee ETC Approved Any steel tracked vehicle equipped with a front mounted blade used for exposing mineral soil.
dozer company Equipment Technology Committee ETC Approved A resource that includes a dozer, its transportation unit and a standard complement of personnel for its operation.
dozer line IOSC Incident Operations Subcommittee Approved Fireline constructed by the front blade of a dozer.
dozer tender Equipment Technology Committee ETC Approved Any ground vehicle with personnel capable of maintenance, minor repairs, and limited fueling of dozers.
draft IOSC Incident Operations Subcommittee Approved Drawing water from static sources such as a lake, pond, cistern, river, etc. into a pump which is above the level of the water supply. This is done by removing the air from the pump and allowing atmospheric pressure [14.7 psi (101 kPa) at sea level] to push water through a noncollapsible suction hose into the pump. 
drain time Equipment Technology Committee ETC Approved The time (minutes) it takes for foam solution to drop out from the foam mass; for a specified percent of the total solution contained in the foam to revert to liquid and drain out of the bubble structure.
draped fuels Fire Use Subcommittee FUSC Approved Needles, leaves, and twigs that have fallen from above and have lodged on lower branches or brush. Draped fuels are part of aerial fuels.
drift Fire Behavior Subcommittee FBSC Approved Effect of wind on smoke, retardant drops, paracargo, smokejumper streamers, etc.
drift smoke Fire Use Subcommittee FUSC Approved Smoke that has drifted from its point of origin and is no longer dominated by convective motion. May give false impression of a fire in the general area where the smoke has drifted.
drip torch Equipment Technology Committee ETC Approved Hand-held device for igniting fires by dripping flaming liquid fuel on the materials to be burned; consists of a fuel fount, burner arm, and igniter. Fuel used is generally a mixture of diesel and gasoline.
drive axle Equipment Technology Committee ETC Approved An axle that supports a portion of the vehicle weight and transmits a driving force to the wheels.
drive wheels Equipment Technology Committee ETC Approved Wheels powered by all of the vehicle's drive axles. Dual tires are considered as single wheels. The number of wheels is commonly referenced by the terms "4x2", "4x4", etc. where the first figure indicates the total number of wheels on the ground and the second figure, the number of drive wheels.
drizzle Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved Precipitation composed exclusively of water drops smaller than 0.02 inches (0.5 mm) in diameter.
drop configuration National Interagency Aviation Committee NIAC Approved The type of retardant drop selected to cover a ground target. Terms that can specify the type of drop configuration include Salvo Drop and Trail Drop.
drop pass IASS Interagency Aerial Supervision Subcommittee Approved Indicates that the airtanker has the target in sight and will make a retardant drop on this run over the target.
drop pattern SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved The distribution of an aerially delivered retardant drop on the target area in terms of its length, width, and momentum (velocity x mass) as it approaches the ground. The latter determines the relative coverage level of the fire retardant on fuels within the pattern. 
Drop Zone (DZ) Interagency Helicopter Operations Subcommittee IHOPS, SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved Target area for airtankers, helitankers, cargo dropping.
drought Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved A period of relatively long duration with substantially below-normal precipitation, usually occurring over a large area.
drought index Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved A number representing the net effect of evaporation, transpiration and precipitation in producing cumulative moisture depletion in deep duff or upper soil layers.
drug paraphernalia Communication, Education, and Prevention Committee CEPC In Development Tools, devices or equipment ued for the consupmtion, preparation, or consealment of drugs. 
drum lifter National Interagency Aviation Committee NIAC Approved Device used to transport a 55-gallon drum (208 L) via sling on a helicopter.
dry Incident Business Committee IBC Approved The government furnishes all operating supplies after the equipment arrives at the incident.
dry adiabatic lapse rate Fire Weather Subcommittee FWS Approved The rate of decrease of temperature with height of a parcel of dry air lifted adiabatically through an atmosphere in hydrostatic equilibrium. Numerically equal to 9.7670 C degrees per km or about 5.40 F degrees per thousand feet.
dry air mass Fire Weather Subcommittee FWS Approved A portion of the atmosphere that has a relatively low dew point temperature and where the formation of clouds, fog, or precipitation is unlikely.
dry bulb Fire Weather Subcommittee FWS Approved A name given to an ordinary thermometer used to determine the temperature of the air (to distinguish it from the wet bulb).
Dry Episode (DE) Fire Weather Subcommittee FWS Approved A contiguous series of days having a pre-established number of fire ignitions with a fuel dryness level that historically resulted in a significant fire event for a particular area.
dry foam Equipment Technology Committee ETC Approved A low expansion foam type with stable bubble structure and slow drain time which is used primarily for resource and property protection.
dry hydrant (natural source) Equipment Technology Committee ETC Approved Permanent devices with fire engine threads attached to expedite drafting operations in locations where there are water sources suitable for use in fire suppression (e.g., piers, wharves, bridges over streams, highways adjacent to ponds).
dry hydrant (suction source) Equipment Technology Committee ETC Approved Permanently installed supply private fire pumps which depend upon suction sources.
dry lightning storm Fire Weather Subcommittee FWS Approved Thunderstorm in which negligible precipitation reaches the ground.
dry run IASS Interagency Aerial Supervision Subcommittee Approved A trial pass over the target area by a leadplane and/or an airtanker to pinpoint target areas and warn ground personnel of the impending retardant or extinguishing agent drop.
dry storage Equipment Technology Committee ETC Approved Refers to dry chemical retardants stored at air attack bases and available for mixing with water.
dry-bulb temperature FDSC Fire Danger Subcommittee Approved The temperature of the air measured in the shade 4-8 feet above the ground.
dry-bulb thermometer Fire Weather Subcommittee FWS Approved In a psychrometer, the thermometer not covered with muslin which is used to determine air temperature.
duff Fire Use Subcommittee FUSC Approved The layer of decomposing organic materials lying below the litter layer of freshly fallen twigs, needles, and leaves and immediately above the mineral soil.
durability (foam) Equipment Technology Committee ETC Approved The effective life span of foam bubbles.
duty week Incident Business Committee IBC Approved Regular number of hours worked per week by a full-time firefighter, excluding overtime.
dynamic grid failure Communication, Education, and Prevention Committee CEPC In Development When a dynamic brake is applied, the traction motors convert to generators which produe electrical current that is routed to a resistor grid on the locamotive. This resistor grid resembles a larg toaster element and its location on an engive varies but is typically vented out the top of the locomotive car body.
earthquake (event) National Coordination System Committee NCSC Approved An event dealing with response to an earthquake.
eddy Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved A circular-like flow of a fluid (such as air or water) drawing its energy from a flow of much larger scale, and brought about by pressure irregularities as in the downwind (lee) side of a solid obstacle. For example, wind conditions may be erratic and may eddy on the downwind side of large rock outcroppings, buildings, etc. 
edge (fuel type) Fire Use Subcommittee FUSC Approved The boundary between two fairly distinct fuel types.
edge (plant community) Fire Use Subcommittee FUSC Approved The place where plant communities meet or where successional stages or vegetative conditions within plant communities come together.
edge firing Fire Use Subcommittee FUSC Approved Method of burning in which fires are set along the edges of an area and allowed to spread inward.
edit name (feature class) Geospatial Subcommittee GSC Approved Name of the person editing the feature.
eductor Equipment Technology Committee ETC Approved A device used to introduce and mix fire chemical into a water stream. An eductor is a fitting with three ports, an inlet for water flow, an outlet for water flow, and an inlet for fire chemical concentrate. The flow of water through the eductor produces a region of lower pressure at the fire chemical inlet, drawing the chemical into the water stream. 
effective windspeed Fire Weather Subcommittee FWS Approved The midflame wind speed adjusted for the effect of slope on fire spread.
ejector Equipment Technology Committee ETC Approved A siphon device used to fill an engine's tank when the water source is below or beyond the engine's drafting capability.
elapsed time IOSC Incident Operations Subcommittee Archived The total time taken to complete any step(s) in fire suppression.
elearning Incident and Position Standards Committee IPSC Archived Conceptually represents the optimum integration of modern educational methods and professional staff development training with state of the art technology. The primary goal is enhancing on-the-job performance, motivation, and learning performance.
electric fence Communication, Education, and Prevention Committee CEPC In Development A fence through which an electric current can be passed thereby giving an electric shock to any person or animal touching it.
electric motor/power tools/battery Communication, Education, and Prevention Committee CEPC In Development A machine that converts electrical energy into mechanical energy.
electrical transmission/distribution systems Communication, Education, and Prevention Committee CEPC In Development
electronic cigarettes Communication, Education, and Prevention Committee CEPC In Development A battery-powered device that simulates the act of smoking by delivering a vaporized form of nicotine and other substances.
elevation (water source) Geospatial Subcommittee GSC Approved Surface elevation in feet at the water source.
elevation feet In Development A geographic location's height above or below a fixed reference point
elevation loss Equipment Technology Committee ETC Approved In hydraulics, the pressure loss caused by raising water through hose or pipe to a higher elevation (roughly equal to one psi for every two-foot increase in elevation above the pump) (11.3 kPa per meter).
emergency National Incident Management System Integration Committee NIMSIC Approved Any incident, whether natural, technological, biological, or human-caused, that necessitates responsive action to protect life or property.
Emergency Equipment Rental Agreement (EERA) Incident Business Committee IBC Approved An agreement written at an incident using an EERA, OF-294. The duration is for the length of the incident only.
Emergency Firefighter (EFF) Incident Business Committee IBC Approved A person employed as an emergency worker on a forest or wildland fire which threatens damage to property under public management. Emergency firefighters are hired for the duration of the emergency only.
Emergency Locator Transmitter (ELT) National Interagency Aviation Committee NIAC Approved A radio transmitter attached to the aircraft structure which operates from its own power source on 121.5 MHz and 243 MHz. The transmitter transmits a distinctive downward swept audio tone for homing purposes and is designed to function without human action after an accident. 
Emergency Management Assistance Compact National Incident Management System Integration Committee NIMSIC Approved A congressionally ratified agreement that provides form and structure to interstate mutual aid. Through EMAC, a disaster-affected state can request and receive assistance from other member states quickly and efficiently, resolving two key issues up front: liability and reimbursement.
emergency operations plan National Coordination System Committee NCSC, National Incident Management System Integration Committee NIMSIC Approved A plan for responding to a variety of potential hazards.
emergency response provider National Incident Management System Integration Committee NIMSIC Archived Any federal, state, or local emergency public safety, law enforcement, emergency responder, emergency medical (including hospital emergency facilities), and related personnel, agencies, and authorities. It is any organization responding to an emergency, or providing mutual aid support to such an organization, whether in the field, at the scene of an incident, or operations center. 
emergency stabilization IFPC Interagency Fire Planning Committee Approved Planned actions to stabilize and prevent unacceptable degradation to natural and cultural resource, to minimize threats to life or property resulting from the effects of a fire, or to repair/replace/construct physical improvements necessary to prevent degradation of land or resources. 
emergency stabilization (event) National Coordination System Committee NCSC Approved An event dealing with emergency response to stabilize land and structures damaged by wildfire with the objective to protect life and property from damage due to post-fire events and fire. Usually occurring 1-12 months from ignition date.
Emergency Support Function (ESF) National Incident Management System Integration Committee NIMSIC Approved The grouping of governmental and certain private sector capabilities into an organizational structure to provide core capabilities and services most likely needed to manage domestic incidents.
emission Fire Use Subcommittee FUSC Approved A release of combustion gases and aerosols into the atmosphere.
Emission Factor (EF) Fire Use Subcommittee FUSC Approved The mass of particulate matter produced per unit mass of fuel consumed (pounds per ton, grams per kilogram).
emission rate Fire Use Subcommittee FUSC Approved The amount, or mass of smoke produced per unit of time. For example: Emission Rate = Available Fuel x Burning Rate x Emission Factor.
emission reduction Fire Use Subcommittee FUSC Approved A strategy for controlling smoke from prescribed fires that minimizes the amount of smoke output per unit area treated.
emission standard Fire Use Subcommittee FUSC Approved A general type of standard that limits the mass of a pollutant that may be emitted by a source. The most straightforward emissions standard is a simple limitation on mass of pollutant per unit time (e.g., pounds of pollutant per hour).
employment category IOSC Incident Operations Subcommittee Approved The employment appointment or agreement under which a person is hired.
empty weight Equipment Technology Committee ETC Approved Weight of an aircraft/engine including the structure, power plant, all fixed equipment, all fixed ballast, unusable fuel, undrainable oil, and total quantity of hydraulic fluid.
Energy Release Component (ERC) Fire Weather Subcommittee FWS Approved The computed total heat release per unit area (British thermal units per square foot) within the flaming front at the head of a moving fire.
engine Equipment Technology Committee ETC Approved Any ground vehicle providing specified levels of pumping, water, and hose capacity but with less than the specified level of personnel.
engine company Equipment Technology Committee ETC Approved A resource that includes an engine of a specific type. The type specifies tank capacity, pump rating, hose capacity and number of personnel.
engine type (water source) National Coordination System Committee NCSC Approved Largest engine type that can use the water source.
entrapment Risk Management Committee RMC Approved A situation where personnel are unexpectedly caught in a fire behavior-related, life-threatening position where planned escape routes or safety zones are absent, inadequate, or compromised. An entrapment may or may not include deployment of a fire shelter for its intended purpose. These situations may or may not result in injury. They include "near misses."
entrapment avoidance Risk Management Committee RMC Approved A process used to improve the safety of personnel on the fireline, which emphasizes tools and tactics available to prevent being trapped in a burnover situation. This process includes appropriate decision making through risk management, application of LCES, use of pre-established trigger points, and recognition of suitable escape routes and safety zones. 
envelopment IOSC Incident Operations Subcommittee Approved Direct attack with multiple anchor points, that allows for multiple points of attack. Generally used as an engine tactic in the wildland urban interface.
environment Fire Weather Subcommittee FWS Approved The complex surroundings of an item or area of interest, such as air, water, natural resources, and their physical conditions (temperature, humidity).
environmental lapse rate Fire Weather Subcommittee FWS Approved The actual rate of decrease of temperature with elevation.
environmental specialist IOSC Incident Operations Subcommittee Archived Person responsible to the planning section chief for collecting and analyzing environmental information about the incident area, determining environmental restrictions and requirements, and providing the information as an input to the incident action and to incident personnel as needed. 
episode (pollution) Fire Use Subcommittee FUSC Approved A condition of poor contaminant dispersion which may result in concentrations considered potentially harmful to health or welfare. Episodes may also occur during periods of fairly good dispersion if the source of air contaminants is extremely large.
Equilibrium Moisture Content (EMC) FDSC Fire Danger Subcommittee Approved Moisture content that a fuel particle will attain if exposed for an infinite period in an environment of specified constant temperature and humidity. When a fuel particle reaches equilibrium moisture content, net exchange of moisture between it and its environment is zero. 
equipment and vehicle use Communication, Education, and Prevention Committee CEPC In Development
equipment use fire Wildland Fire Investigation Subcommittee WFISC Approved Fire caused by mechanical equipment other than railroad operations.
escape route Risk Management Committee RMC Approved A preplanned and understood route firefighters take to move to a safety zone or other low-risk area. When escape routes deviate from a defined physical path, they should be clearly marked (flagged).
escaped fire IOSC Incident Operations Subcommittee Approved Fire which has exceeded or is expected to exceed initial attack capabilities or prescription.
escaped prescribed fire FRSC Fire Reporting Subcommittee, Fuels Management Committee FMC Proposed New a prescribed fire that has exceeded or is expected to exceed prescription parameters or otherwise meets the criteria for conversion to wildfire
escaped prescribed fire Communication, Education, and Prevention Committee CEPC In Development A prescribed fire that has exceeded or is expected to exceed prescription parameters or otherwise meets the criteria for conversion to wildfire.
ESF Coordinator National Incident Management System Integration Committee NIMSIC Approved An entity which oversees the preparedness activities for a particular ESF and coordinates with its primary and support agencies.
ESF Primary Agency National Incident Management System Integration Committee NIMSIC Approved A Federal agency with significant authorities, roles, resources, and capabilities for a particular function within an ESF.
ESF Support Agency National Incident Management System Integration Committee NIMSIC Approved An entity with specific capabilities or resources that support the primary agencies in executing the mission of the ESF.
estimated containment date FRSC Fire Reporting Subcommittee Approved The expected containment or completion date of the incident.
estimated incident cost Incident Business Committee IBC Approved Estimated dollar amount associated with an incident.
Estimated Position Error (EPE) Wildland Fire Investigation Subcommittee WFISC Approved A measurement of horizontal position error for a GPS unit expressed in feet or meters.
Estimated Time En Route (ETE) National Coordination System Committee NCSC, Incident Business Committee IBC Approved Term used in resource planning/following to estimate time spent between points.
Estimated Time of Arrival (ETA) National Coordination System Committee NCSC, Incident Business Committee IBC Approved Term used in resource planning/following to estimate time of arrival at a point.
Estimated Time of Departure (ETD) National Coordination System Committee NCSC, Incident Business Committee IBC Approved Term used in resource planning/following to estimate time of departure from a point.
evacuation National Incident Management System Integration Committee NIMSIC Approved The organized, phased, and supervised withdrawal, dispersal, or removal of people and/or animals from dangerous or potentially dangerous areas, and their reception and care in safe areas.
evaluate FMB Fire Management Board Approved To review and compare outcomes with management and incident objectives desired for a wildland fire. One of the six component activities in an adaptive management process that may lead to adjusting future actions.
evaluation (resource) IOSC Incident Operations Subcommittee Approved A description of how the resource performed on an incident. The evaluation is focused on the specific capacity the resource was required to perform.
evaluation timestamp (resource) Incident and Position Standards Committee IPSC The date/time the trainee experience was evaluated.
evaluator Incident and Position Standards Committee IPSC Approved The individual who is qualified in the position being evaluated, or supervises the position being evaluated, having responsibility for observing task(s) being performed and documenting successful performance for agency certification or re-certification. Evaluator responsibilities must remain separate from the individual assigned as Trainer/Coach. 
evaporation Fire Weather Subcommittee FWS Approved The transformation of a liquid to its gaseous state; heat is released by the liquid during this process.
event (generic) National Coordination System Committee NCSC Approved A generic term that relates to both planned and unplanned response activities by the interagency wildland fire community.
event (planned) National Incident Management System Integration Committee NIMSIC Approved An incident that is a scheduled non-emergency activity (e.g., sporting event, concert, parade).
evidence protection area Wildland Fire Investigation Subcommittee WFISC Approved An area where evidence or potential evidence is or may be located and should be secured and protected from unauthorized entry.
exempt / nonexempt Incident Business Committee IBC Approved Categories of employees as defined in the Fair Labor Standards Act (FLSA), who are either covered or exempted from coverage under the ActPay entitlements vary depending on the employee's FLSA status.
exhaust particles Communication, Education, and Prevention Committee CEPC In Development Diesel carbon is bound together with polymeric lubricant resins and form particles with pumice-like, granular, or flaky appearence which is often sooty or oily.
exhaust primer Equipment Technology Committee ETC Approved Device which uses the exhaust gas flow of an engine for priming a centrifugal pump.
expanded dispatch Incident Business Committee IBC Approved An organization needed to support an incident which expands along with the Incident Command System.
expansion Equipment Technology Committee ETC Approved The ratio of the volume of the foam in its aerated state to the original volume of the non-aerated foam solution.
experience IOSC Incident Operations Subcommittee Proposed New Documented performance in a position.
experience from date Incident and Position Standards Committee IPSC Approved The time when the Experience began.
experience to date Incident and Position Standards Committee IPSC Approved The time when the Experience ended.
expert witness Wildland Fire Investigation Subcommittee WFISC Approved Someone with sufficient skill, knowledge, or experience in a given field so as to be capable of drawing inferences or reaching conclusions or opinions that an average person would not be competent to reach. The expert's opinion testimony should aim the judge or jury in their understanding of the fact at issue. 
exploding target shooting Communication, Education, and Prevention Committee CEPC Superceded
exploding targets
explosives or electrical danger (event) National Coordination System Committee NCSC Approved An event dealing with the various situations that arise as a result of an explosion, presence of an explosive device, or electrical hazard - no fire. 
exposed side Wildland Fire Investigation Subcommittee WFISC Approved The side of an object facing the oncoming fire.
exposure (direction) Fire Environment Committee FENC Approved Direction in which a slope faces, usually with respect to cardinal directions.
exposure (openness) Fire Environment Committee FENC Approved The general surroundings of a site with special reference to its openness to winds.
exposure (threatened) Fire Environment Committee FENC Approved Property that may be endangered by a fire burning in another structure or by a wildfire.
exposure fire IOSC Incident Operations Subcommittee Approved Classification for a fire not originating in a building, but which ignites building(s). A fire originating in one building and spreading to another is classified under the original cause of fire.
extend Equipment Technology Committee ETC Approved To drop retardant in such a way that the load slightly overlaps and links a previous drop. "Extend your last drop."
extended attack IOSC Incident Operations Subcommittee Approved Actions taken on a wildfire that has exceeded the initial response.
extended attack incident IOSC Incident Operations Subcommittee Approved An incident that exceeds the capability of the initial attack resources and/or organization to successfully manage the incident to conclusion.
exterior fire protection IOSC Incident Operations Subcommittee Approved The protection of structures from the exterior, with no interior access or activity.
external load National Interagency Aviation Committee NIAC Approved A load that is carried or extends outside of the aircraft fuselage.
external payload National Interagency Aviation Committee NIAC Approved Maximum external stress load (in pounds) with full fuel and pilot in calm air at standard atmospheric temperature.
extinguishing agent Equipment Technology Committee ETC Approved Substance used to put out a fire by cooling the burning material, blocking the supply of oxygen, or chemically inhibiting combustion.
extra burning period IOSC Incident Operations Subcommittee Approved For any particular fire which is neither contained nor controlled, any 24-hour period following the termination of the first burning period.
extreme fire behavior Fire Behavior Subcommittee FBSC Approved Extreme implies a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning and/or spotting, presence of fire whirls, strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously. 
eyewitness Wildland Fire Investigation Subcommittee WFISC Approved Person who sees evidence of criminal activity, actual commission of a crime or a criminal fleeing a crime scene.
Facilities Unit National Incident Management System Integration Committee NIMSIC Approved Facilities Unit staff set up, maintain, and demobilize all facilities used in support of incident operations. This staff provides facility maintenance and law enforcement/security services needed for incident support. Facilities Unit staff set up the Incident Command Post (ICP), Incident Base, and camps (including trailers or other forms of shelter in and around the incident area) and ensure the maintenance of those facilities. This unit’s staff provide and maintain personnel support facilities, including areas for eating, sleeping, sanitation and showers, and staging. Staff in this unit order additional support items such as portable toilets, shower facilities, and lighting units through the Supply Unit.
fahrenheit Fire Weather Subcommittee FWS Approved A temperature scale on which 320 F denotes the temperature of melting ice, and 2120 F the temperature of boiling water, both under standard atmospheric pressure.
faller Hazard Tree and Felling Subcommittee HTTFS Approved A person who fells trees.
faller module National Coordination System Committee NCSC, Hazard Tree and Felling Subcommittee HTTFS Pending Revision Two agency qualified sawyers specially trained and equipped to conduct saw operations in moderate and high complexity situations.
False Alarm (FA) (event) National Coordination System Committee NCSC Approved An event where a wildfire was initially suspected, but ultimately an ignition could not be located; or the basis for the initial report was subsequently attributed to a non-fire source, such as water vapor or vented industrial emissions. The key point here is No FIRE, an incident cannot be a false alarm if an ignition is located.
family liaison Risk Management Committee RMC Approved The primary contact between the agency and the victim’s family
feature access Geospatial Subcommittee GSC Approved Determines who or what groups can view a particular feature.
feature category Geospatial Subcommittee GSC Approved Type of wildland fire polygon or unburned areas
Federal Aviation Regulation (FAR) National Interagency Aviation Committee NIAC Approved Refers to the regulations governing all aviation activities of civil aircraft within the United States and its territories.
Federal Coordinating Officer (FCO) Incident Business Committee IBC Approved The person appointed by the President to coordinate federal assistance in the designated area following the declaration of a major disaster or emergency under the Stafford Act.
federal fire policy FMB Fire Management Board Approved Principles and policies providing a common approach to wildland fire for federal agencies. The primary, interagency wildland fire policy document is the "Review and Update of the 1995 Federal Wildland Fire Management Policy" (January 2001). Implementation of that policy is through the "Guidance for Implementation of Federal Wildland Fire Management Policy" (February 2009).
Federal Wage System Employee Incident Business Committee IBC Approved Regular federal government employee who is compensated under the Federal Wage System and referred to as Wage Grade (WG), Wage Leader (WL), or Wage Supervisor (WS) employee.
female coupling Equipment Technology Committee ETC Approved Coupling made to receive a male coupling of the same thread, pitch and/or diameter.
field test Risk Management Committee RMC Approved A job-related test of work capacity designed for those with moderately strenuous duties. This test consists a two-mile hike with a 25-pound pack. A time of 30 minutes, the passing score for this test, approximates an aerobic fitness score of 40.
field training Training Delivery Committee TDC Approved Instructor-led training that is conducted in field environment.
field/agricultural burning Communication, Education, and Prevention Committee CEPC In Development The practice of intentionally setting fire to unwanted vegetation in a field, typically crop residue left after harvest, to clear the land for new planting, manage pests, or control weeds.
fill tank Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Large, portable tank from which helitankers can hoverfill.
filling Fire Weather Subcommittee FWS Approved An increase in the central pressure of a low. Counter-clockwise wind flow around the low usually decreases as filling occurs.
final acres Approved Number of acres within the final fire perimeter of a specific, individual incident, including unburned and unburnable islands.
final approach National Interagency Aviation Committee NIAC Approved Flight path in the direction of the landing along the extended runway center line from the base leg to the runway.
final evaluator Incident and Position Standards Committee IPSC Approved The individual responsible for completing the position task book's verification statement once all tasks in the position task book have been completed and signed off. Only the evaluator on the final position performance assignment (the assignment in which all remaining tasks have been evaluated and signed off) will complete the verification statement recommending certification. 
final fire size FRSC Fire Reporting Subcommittee Approved Number of acres within the final fire perimeter of a specific, individual incident, including unburned and unburnable islands.
final run National Interagency Aviation Committee NIAC Approved An airtanker is "on final" when it is on line with the target and intends to make the drop on that pass; also applies to cargo dropping.
Finance/Administration Section National Incident Management System Integration Committee NIMSIC, Incident Business Committee IBC Approved The ICS Section responsible for an incident’s administrative and financial considerations.
fine fuel moisture FDSC Fire Danger Subcommittee Approved The probable moisture content of fast-drying fuels which have a timelag constant of 1 hour or less; such as, grass, leaves, ferns, tree moss, pine needles, and small twigs (0-1/4").
fine fuels Fire Use Subcommittee FUSC Approved Fast-drying dead or live fuels, generally characterized by a comparatively high surface area-to-volume ratio, which are less than 1/4-inch in diameter and have a timelag of one hour or less. These fuels (grass, leaves, needles, etc.) ignite readily and are consumed rapidly by fire when dry.
fingers of a fire Fire Environment Committee FENC Approved The long narrow extensions of a fire projecting from the main body.
fire Wildland Fire Investigation Subcommittee WFISC Approved Rapid oxidation, usually with the evolution of heat and light; heat fuel, oxygen and interaction of the three.
fire (event) National Coordination System Committee NCSC Approved An event, managed by the wildland fire community, where an ignition resulting in sustained combustion occurred.
Fire Adapted Community (FAC) WMSC WUI Mitigation Subcommittee Approved A community that recognizes its risk and takes action before, during and after a fire in order for their community to be more resilient to wildfire. Fire adapted community members are informed and prepared, collaboratively planning and taking action to better live with wildland fire.
fire agency Incident Business Committee IBC Approved Official group or organization compelled and authorized under statutes or law to control fires within a designated area or upon designated lands.
fire behavior Fire Behavior Subcommittee FBSC Approved The manner in which a fire reacts to the influences of fuel, weather, and topography.
fire behavior context Wildland Fire Investigation Subcommittee WFISC Approved The fuels, weather and topographical conditions of a specific fire scene or area of the fire scene at the time of fire passage.
fire behavior forecast Fire Behavior Subcommittee FBSC Approved Prediction of probable fire behavior, usually prepared by a fire behavior analyst, in support of fire suppression or prescribed burning operations.
fire behavior prediction model Fire Behavior Subcommittee FBSC Approved A set of mathematical equations that can be used to predict certain aspects of fire behavior when provided with an assessment of fuel and environmental conditions.
fire behavior prediction system Fire Behavior Subcommittee FBSC Approved A system that uses a set of mathematical equations to predict certain aspects of fire behavior in wildland fuels when provided with data on fuel and environmental conditions.
fire benefits Fire Use Subcommittee FUSC Approved Fire effects with positive monetary, social, or emotional value or that contribute, through changes in the resource base, to the attainment of organizational goals.
fire bug Wildland Fire Investigation Subcommittee WFISC Approved Arsonist, especially a repetitive firesetter.
fire business FDSC Fire Danger Subcommittee Approved The characterization of fire occurrence in an area, described in terms of total number of fires and acres per year; and number of fires by time, size, cause, fire-day, large fire-day, and multiple fire-day.
fire business thresholds FDSC Fire Danger Subcommittee Approved Values of one or more fire weather/fire danger indexes that have been statistically related to occurrence of fires (fire business). Generally the threshold is a value, or range of values where historical fire activity has significantly increased or decreased. 
fire cache Equipment Technology Committee ETC Approved A supply of fire tools and equipment assembled in planned quantities or standard units at a strategic point for exclusive use in fire suppression.
fire cause Communication, Education, and Prevention Committee CEPC, Wildland Fire Investigation Subcommittee WFISC Approved Agency or circumstance which started a fire or set the stage for its occurrence; source of a fire's ignition. For statistical purposes fires are grouped into broad cause classes. The nine general causes used in the U.S. are lightning, campfire, smoking, debris burning, incendiary, machine use (equipment), railroad, children, and miscellaneous. 
fire cause class Wildland Fire Investigation Subcommittee WFISC Approved Any class into which wildland fires are grouped according to their origin.
fire climate FDSC Fire Danger Subcommittee Approved Composite pattern of weather elements over time that affect fire behavior in a given region.
fire climax Fire Use Subcommittee FUSC Approved Plant community maintained by periodic fires.
fire containment date time FRSC Fire Reporting Subcommittee Approved The date and time a wildfire was declared contained.
fire control date time FRSC Fire Reporting Subcommittee Approved The date and time a wildfire was declared under control.
fire crew IOSC Incident Operations Subcommittee Approved General term for two or more firefighters organized to work as a unit.
fire crew work formation IOSC Incident Operations Subcommittee Approved Standard crew arrangement used for fireline construction in direct or indirect attack; consists of line locator, line cutters, rakers, torch operators, and mop up crew.
fire danger FDSC Fire Danger Subcommittee Approved Sum of constant danger and variable danger factors affecting the inception, spread, and resistance to control, and subsequent fire damage; often expressed as an index.
fire danger continuum FDSC Fire Danger Subcommittee Approved The range of possible values for a fire danger index or component, given a set of NFDRS parameters and weather input.
fire danger index FDSC Fire Danger Subcommittee Approved A relative number indicating the severity of wildland fire danger as determined from burning conditions and other variable factors of fire danger.
fire danger rating FDSC Fire Danger Subcommittee Approved A fire management system that integrates the effects of selected fire danger factors into one or more qualitative or numerical indices of current protection needs.
fire danger rating area FDSC Fire Danger Subcommittee Approved A geographic area of relatively homogenous climate, fuels and topography, tens of thousands of acres in size, within which the fire danger can be assumed to be uniform. The basic on-the-ground unit for which unique fire management decisions are made based on fire danger ratings. Weather is represented by one or more NFDRS weather stations. 
Fire Danger Rating Operating Plan FDSC Fire Danger Subcommittee Approved A guide to collection, communication, and application of fire danger ratings at the local level.
Fire Danger Rating Pocket Card for Firefighter Safety FDSC Fire Danger Subcommittee Approved A communication aid designed to help firefighters develop an awareness of the local fire situation by providing a visual reference to fire danger rating.
Fire Danger Rating System FDSC Fire Danger Subcommittee Approved The complete program necessary to produce and apply fire danger ratings, including data collection, data processing, fire danger modeling, communications, and data storage.
fire death Risk Management Committee RMC Approved Fire casualty which is fatal or becomes fatal within one year of the fire.
fire dependent Fire Use Subcommittee FUSC Approved Plants and vegetation communities which have evolved adaptations such as a reliance on fire as a disturbance agent, protection as a species against the effects of wildland fire, or even a strengthening or enhancement by it.
fire detection IOSC Incident Operations Subcommittee Approved The act or system of discovering and locating fires.
fire detection (automated) FRSC Fire Reporting Subcommittee Approved A fire detected via artificial intelligence using computer-vision to monitor fire starts and send notification without human interpretation.
fire detection (manual) FRSC Fire Reporting Subcommittee Approved A fire detected by a human actively viewing the fire camera footage.
fire diagram Wildland Fire Investigation Subcommittee WFISC Approved A near scale depiction of the scene based on measurements and data.
fire discovery Data Management Committee DMC Approved The act of determining that a fire exists; does not include determining its location.
fire discovery date Approved The day the fire was confirmed to exist or was reported as discovered.
fire discovery date time FRSC Fire Reporting Subcommittee Approved The date and time a fire was discovered or confirmed to exist.
fire discovery time FRSC Fire Reporting Subcommittee Approved The time of day the fire was confirmed to exist or was reported as discovered.
fire district IOSC Incident Operations Subcommittee Archived A rural or suburban fire organization, usually tax supported, that maintains fire companies and apparatus.
fire duty IOSC Incident Operations Subcommittee Archived Actual physical engagement in firefighting service as distinguished from staff work at headquarters or maintenance division; work at an individual fire done by an individual firefighter or by a company.
fire ecology Fire Use Subcommittee FUSC Approved The study of the effects of fire on living organisms and their environment.
fire edge Fire Use Subcommittee FUSC Approved The boundary of a fire at a given moment.
fire education Communication, Education, and Prevention Committee CEPC Approved Activities to change behaviors and attitudes about fire ecology, wildland fire and the role of fire in natural resource management. Defines the purposes for actions that provide information about and improve understanding of wildland fire.
fire effects Fire Use Subcommittee FUSC Approved The physical, biological, and ecological impacts of fire on the environment.
fire environment Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved The surrounding conditions, influences, and modifying forces of topography, fuel, and weather that determine fire behavior.
fire frequency FDSC Fire Danger Subcommittee, Fire Use Subcommittee FUSC Approved A general term referring to the recurrence of fire in a given area over time.
fire front Fire Behavior Subcommittee FBSC Approved The part of a fire within which continuous flaming combustion is taking place. Unless otherwise specified, the fire front is assumed to be the leading edge of the fire perimeter. In ground fires, the fire front may be mainly smoldering combustion.
fire guard IOSC Incident Operations Subcommittee Archived A general term for a firefighter, lookout, patrol, prevention guard, or other person directly employed for prevention and/or detection and suppression of fires.
fire hazard FDSC Fire Danger Subcommittee Approved A fuel complex, defined by volume, type condition, arrangement, and location, that determines the degree of ease of ignition and of resistance to control.
fire hazard index FDSC Fire Danger Subcommittee Approved A numerical rating for specific fuel types, indicating the relative probability of fires starting and spreading, and the probable degree of resistance to control; similar to burning index, but without effects of wind speed.
fire hazardous areas Fire Behavior Subcommittee FBSC Approved Those wildland areas where the combination of vegetation, topography, weather, and the threat of fire to life and property create difficult and dangerous problems.
fire history Wildland Fire Investigation Subcommittee WFISC Approved A general term referring to the historic fire occurrence of a given geographic area.
fire initial action date-time FRSC Fire Reporting Subcommittee Approved The date and time that initial action was taken by the first resources to arrive at a fire.
fire initial action time FRSC Fire Reporting Subcommittee Approved The time that initial response action was taken by the first resources to arrive at a wildfire or wildland fire use incident.
fire injury Incident Business Committee IBC, Risk Management Committee RMC Approved Injury suffered as the result of a fire that requires (or should require) treatment by a practitioner of medicine within one year of the fire, regardless of whether treatment was actually received.
fire inspector Wildland Fire Investigation Subcommittee WFISC Approved Fire prevention specialist or arson investigator.
Fire Intensity Level (FIL) code (Point of Origin) (POO) Fire Behavior Subcommittee FBSC, Fire Environment Committee FENC Approved An expression of fire intensity based on observed and/or calculated flame lengths representative across the immediate vicinity of the point of origin during the initial response.    Fire intensity levels (FILs) provide "an expression of fireline intensity, based on typical and/ or calculated flame length of a fire behavior condition. FILs are used in the analysis to reflect the differences in difficulty of suppression and fire effects on natural and cultural resources." (Ref. FSH5109.19 ch40.5 9/85)
fire interval Fire Use Subcommittee FUSC Approved The number of years between two successive fire events for a given area; also referred to as fire-free interval or fire-return interval.
fire investigation Wildland Fire Investigation Subcommittee WFISC Approved The process of determining the ignition source, materials first ignited, ignition factors, and party responsible for a fire.
fire lane Incident and Position Standards Committee IPSC Archived Cleared path wide enough to permit single-lane vehicular access in a remote area.
fire load FDSC Fire Danger Subcommittee Approved The number and size of fires historically experienced on a given unit over a given period (usually one day) at a given index of fire danger.
Fire Load Index (FLI) FDSC Fire Danger Subcommittee Approved Numerical rating of the maximum effort required to contain all probable fires occurring within a rating area during the rating period.
fire management Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved All activities for the management of wildland fires to meet land management objectives. Fire management includes the entire scope of activities from planning, prevention, fuels or vegetation modification, prescribed fire, hazard mitigation, fire response, rehabilitation, monitoring and evaluation. 
fire management action (event) National Coordination System Committee NCSC Approved An event, responded to and/or managed by the wildland fire management community, which addresses certain activities and responses undertaken by the wildland fire management community in conjunction with existing or potential fire event(s).
fire management area Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved One or more parcels of land having a common set of fire management objectives.
fire management improvements Fire Use Subcommittee FUSC Approved All structures built and used primarily for fire management, e.g. lookout towers, lookout cabins, telephone lines, and also firebreaks, fuel breaks, and roads to lookouts.
fire management objective Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved Planned, measurable result desired from fire protection and use based on land management goals and objectives.
Fire Management Plan (FMP) FMB Fire Management Board Approved A compilation of goals, objectives, and requirements from the land/resource management planning process necessary to implement wildland fire management decisions.
Fire Management Unit (FMU) Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved A land area definable by specified management objectives, constraints, topographic features, access, values to be protected, political boundaries, fuel types, major fire regime groups, and other defined elements that set it apart from an adjacent area. The primary purpose of developing Fire Management Units in fire management planning is to assist in organizing information in complex landscapes. A fire management unit may have dominant management objectives and pre-selected strategies assigned to accomplish these objectives. 
fire occurrence identifier Geospatial Subcommittee GSC Approved Globally Unique Identifier (GUID) assigned to the spatialrecord.
fire out date time FRSC Fire Reporting Subcommittee Approved The date when all observable combustion has ceased or there is no risk of the fire again becoming active and requiring additional control or management actions.
fire out time FRSC Fire Reporting Subcommittee Approved The time when all observable combustion has ceased or there is no risk of the fire again becoming active and requiring additional control or management actions. All management activities directly relating to suppression (including mop-up), monitoring, or burning efforts have concluded; however, there may be secondary management efforts, such as burned area rehabilitation or hazard mitigation, still in process.
fire pack Equipment Technology Committee ETC Approved A one-person unit of fire tools, equipment, and supplies prepared in advance for carrying on the back.
fire pattern Wildland Fire Investigation Subcommittee WFISC Approved The visible or measurable physical changes formed by a fire effect or group of fire effects. This can be over a small area or it can include the overall pattern of fire spread as determined by the entirety of fire pattern indicators over a larger area.
fire pattern indicator Wildland Fire Investigation Subcommittee WFISC Approved A physical object that displays changes (fire effects) from exposure to heat, flame, and combustion by-products that can reveal the direction of fire progression at a precise location with accurate analysis. A fire pattern indicator is a single component of the overall fire pattern.
fire pattern indicator cluster Wildland Fire Investigation Subcommittee WFISC Approved Multiple fire pattern indicators in relatively close proximity to each other which exhibit a consistent vector.
fire pattern indicator, angle of char Wildland Fire Investigation Subcommittee WFISC Approved Angled or horizontal char or scorch pattern created on standing fuels as fire burns up to, past and beyond, indicating the direction of fire progression at that point. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, angle of scorch Wildland Fire Investigation Subcommittee WFISC Approved Scorch pattern left on canopy of standing fuels that indicates the direction of fire progression at that point. This fire pattern indicator is included within the fire pattern indicator category of Angle of Char.
fire pattern indicator, cupping Wildland Fire Investigation Subcommittee WFISC Approved A concave or cup-shaped char pattern found on the side of fuels exposed to the oncoming fire including small stumps (generally 10 inch diameter and less are more reliable), grass stem ends and terminal ends of brush and tree limbs (generally less than 1/2 inch diameter) that indicate the direction of fire progression at that point. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, curling FDSC Fire Danger Subcommittee, Wildland Fire Investigation Subcommittee WFISC, Fire Use Subcommittee FUSC Approved Green leaves and succulents, uncured vegetation which bends and curls inwards towards the heat source due to desiccation. One of the 11 NWCG categories of fire pattern indicator.
fire pattern indicator, foliage freeze Wildland Fire Investigation Subcommittee WFISC Approved Small branches, needles, and leaves swept into a position by the wind and fixed by desiccation indicating the wind direction at the time of fire passage. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, grass stem Wildland Fire Investigation Subcommittee WFISC Approved The un-consumed grass stems and heads of cured grass left lying on the ground after the passage of a fire that under certain circumstances point in the direction that the fire came from. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, protection Wildland Fire Investigation Subcommittee WFISC Approved A combustible or non-combustible object that displays differential damage or deposits on opposing sides due to the passage of the fire and indicates the direction of fire progression at that location.  One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, spalling (exfoliation) Wildland Fire Investigation Subcommittee WFISC Approved Rock or boulders that display more chipping or pitting on the exposed surface than the protected surface due to the passage of the fire indicating the direction of fire progression at that location. One of the 11 NWCG categories of fire pattern indicators
fire pattern indicator, staining Wildland Fire Investigation Subcommittee WFISC Approved Objects displaying more stain deposits on the exposed surface of the object than on the protected surface of the object indicating the direction of fire progression at that location. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, u or v Wildland Fire Investigation Subcommittee WFISC Approved Fire pattern that resembles a U or V shape and indicates the direction of fire progression in that area. One of the 11 NWCG categories of fire pattern indicators.
fire pattern indicator, white ash Wildland Fire Investigation Subcommittee WFISC Approved There are two subsets of the white ash fire indicator, deposits and exposure. Objects displaying more white ash deposits on the exposed surface of the object as opposed to the protected surface of the object indicating the direction of fire progression at that location. Objects displaying more attached white ash on the exposed surface of the object as opposed to the protected surface of the object indicating the direction of fire progression at that location. One of the 11 NWCG categories of fire pattern indicators.
fire perimeter Fire Behavior Subcommittee FBSC Approved The entire outer edge or boundary of a fire.
fire planning IFPC Interagency Fire Planning Committee Approved The process of developing and interpreting goals and objectives necessary to guide wildland fire management actions.
Fire Planning Unit (FPU) Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved The geographic scope of the landscape defined for the fire management analysis. A Fire Planning Unit consists of one or more Fire Management Units. FPUs may relate to a single administrative unit, a sub-unit, or any combination of units or sub-units. FPUs are scalable and may be contiguous or non-contiguous. FPUs are not predefined by agency administrative unit boundaries, and may relate to one or more agencies. They may be described spatially. 
fire plow Equipment Technology Committee ETC Approved A heavy duty plowshare or disc plow usually pulled by a tractor to construct a fireline.
fire potential Fire Weather Subcommittee FWS Approved The likelihood of a wildland fire event measured in terms of anticipated occurrence of fire(s) and management's capability to respond. Fire potential is influenced by a sum of factors that includes fuel conditions (fuel dryness and/or other inputs), ignition triggers, significant weather triggers, and resource capability. 
fire presuppression IFPC Interagency Fire Planning Committee Approved Activities undertaken in advance of fire occurrence to help ensure more effective fire suppression. Activities includes overall planning, recruitment and training of fire personnel, procurement and maintenance of firefighting equipment and supplies, fuel treatment and creating, maintaining, and improving a system of fuel breaks, roads, water sources, and control lines. 
fire prevention Communication, Education, and Prevention Committee CEPC Approved Activities such as public education, community outreach, law enforcement, engineering, and reduction of fuel hazards that are intended to reduce the incidence of unwanted human-caused wildfires and the risks they pose to life, property or resources.
fire progress map Geospatial Subcommittee GSC Approved A map maintained on a large fire to show at given times the location of the fire, deployment of suppression forces, and progress of suppression.
fire progression Wildland Fire Investigation Subcommittee WFISC Approved The spread of the fire from one location to another.
fire qualifications Incident and Position Standards Committee IPSC Approved Computerized interagency summary of fire suppression qualifications of listed personnel. Available information includes fire training record, fire experience record, and physical fitness testing score for each individual.
fire regime Fire Use Subcommittee FUSC Approved Description of the patterns of fire occurrences, frequency, size, severity, and sometimes vegetation and fire effects as well, in a given area or ecosystem. A fire regime is a generalization based on fire histories at individual sites. Fire regimes can often be described as cycles because some parts of the histories usually get repeated, and the repetitions can be counted and measured, such as fire return interval. 
fire regime current condition class Fire Use Subcommittee FUSC Approved A qualitative measure classified into three classes describing the relative degree of departure from historical fire regimes, possibly resulting in alterations of key ecosystem components such as species composition, structural stage, stand age, canopy closure, and fuel loadings. 
fire regime groups Fire Use Subcommittee FUSC Approved A classification of fire regimes into a discrete number of categories based on frequency and severity. The national, coarse-scale classification of fire regime groups commonly used includes five groups: I - frequent (0-35 years), low severity; II - frequent (0-35 years), stand replacement severity; III - 35-100+ years, mixed severity; IV - 35-100+ years, stand replacement severity; and V - 200+ years, stand replacement severity. 
fire rehabilitation (event) National Coordination System Committee NCSC Approved An event dealing with objectives to repair damage or disturbance caused by wildfire. Efforts occurring 1-5 years from ignition date.
fire report FRSC Fire Reporting Subcommittee Approved An official record of a fire, generally including information on cause, location, action taken, damage, costs, etc., from start of the fire until completion of suppression action. These reports vary in form and detail from agency to agency.
fire report approver name FRSC Fire Reporting Subcommittee Approved Name of the person that approved the fire report. Approval authority varies by agency.
fire report provider name FRSC Fire Reporting Subcommittee Approved Name of person that provided the data for the fire report or is the contact for questions regarding the fire report.
fire reporting agency unit identifier FRSC Fire Reporting Subcommittee Approved The unit identifier for the agency preparing the fire report.
fire resistant tree Fire Use Subcommittee FUSC Approved A species with compact, resin-free, thick corky bark and less flammable foliage that has a relatively lower probability of being killed or scarred by a fire than a fire sensitive tree.
fire resource category National Coordination System Committee NCSC Approved The intermediate classification of operational resources available to respond to a fire.
fire resource kind National Coordination System Committee NCSC Approved The most general classification of operational resources available to respond to a fire.
fire resource status (record) National Coordination System Committee NCSC Approved Indicates if the resource record being submitted or updated is an initial response resource or daily resource record.
fire resource type National Coordination System Committee NCSC Approved The most specific classification of operational resources available to respond to a fire.
fire resources Incident Business Committee IBC Approved All personnel and equipment available or potentially available for assignment to incidents.
fire restriction polygon In Development A polygon depicting areas where measures have been taken by jurisdictional agencies to impose bans and standards of use on certain human acitvities that could lead to the cause of wildlland fire.
fire retardant Equipment Technology Committee ETC Approved Any substance except plain water that by chemical or physical action reduces flammability of fuels or slows their rate of combustion.
fire risk (agent) Wildland Fire Investigation Subcommittee WFISC Approved A causative agent.
fire risk (likelihood) Wildland Fire Investigation Subcommittee WFISC Approved The chance of fire starting, as determined by the presence and activity of causative agents.
fire risk (potential) Wildland Fire Investigation Subcommittee WFISC Approved A number related to the potential number of firebrands to which a given area will be exposed during the rating day.
fire scar (landscape) Fire Use Subcommittee FUSC Approved The mark left on a landscape by fire.
fire scar (vegetation) Fire Use Subcommittee FUSC Approved A healing or healed injury or wound to woody vegetation, caused or accentuated by a fire.
fire scar analysis Fire Use Subcommittee FUSC Approved Analysis of one or more fire scars to determine individual tree fire frequency or mean fire intervals for specified areas.
fire season (likelihood) Fire Weather Subcommittee FWS Approved Period(s) of the year during which wildland fires are likely to occur, spread, and affect resources values sufficient to warrant organized fire management activities.
fire season (regulated) Fire Weather Subcommittee FWS Approved A legally enacted time during which burning activities are regulated by federal, state or local authority.
fire sensitive tree Fire Use Subcommittee FUSC Approved A species with thin bark or highly flammable foliage that has a relatively greater probability of being killed or scarred by a fire.
fire service IOSC Incident Operations Subcommittee Archived The organized fire protection service; its members, individually and collectively; allied organizations assisting protection agencies.
fire severity Fire Use Subcommittee FUSC Approved Degree to which a site has been altered or disrupted by fire; loosely, a product of fire intensity and residence time.
fire shelter Equipment Technology Committee ETC, Risk Management Committee RMC Approved An aluminized cloth tent that offers protection in a fire entrapment situation by reflecting radiant heat and providing a volume of breathable air.
fire shelter deployment Risk Management Committee RMC Approved Removing a fire shelter from its case and unfolding it to use as protection against heat, smoke, and burning embers.
fire shelter deployment site Risk Management Committee RMC Approved Immediate area where a fire shelter has been deployed.
fire shovel Equipment Technology Committee ETC Approved Type of shovel specifically designed for use in constructing a fireline; has a tapered blade with both edges sharpened for scraping, digging, grubbing, cutting, and throwing.
fire simulator Incident and Position Standards Committee IPSC Archived Training device that imposes simulated fire and smoke on a landscape image, for the purpose of instructing fire suppression personnel in different fire situations and fire suppression techniques.
fire size class code FRSC Fire Reporting Subcommittee Approved A code that corresponds to one of several ranges of fire size based on the number of acres within the final fire perimeter.
fire sketch Wildland Fire Investigation Subcommittee WFISC Approved A not to scale drawing.
fire spread model Fire Behavior Subcommittee FBSC Approved A set of physics and empirical equations that form a mathematical representation of the behavior of fire in uniform wildland fuels.
fire storm Fire Behavior Subcommittee FBSC Approved Violent convection caused by a large continuous area of intense fire. Often characterized by destructively violent surface indrafts, near and beyond the perimeter, and sometimes by tornado-like whirls.
fire suppressant Equipment Technology Committee ETC Approved Any agent used to extinguish the flaming and glowing phases of combustion by direct application to the burning fuel.
fire suppression IOSC Incident Operations Subcommittee Approved All work and activities connected with control and fire-extinguishing operations, beginning with discovery and continuing until the fire is completely extinguished.
fire suppression organization (area) IOSC Incident Operations Subcommittee Approved The personnel responsible for fire suppression within a specified area.
fire suppression organization (fire) IOSC Incident Operations Subcommittee Approved The personnel and equipment collectively assigned to the suppression of a specific fire or group of fires.
fire suppression organization (management structure) IOSC Incident Operations Subcommittee Approved The management structure, usually shown in the form of an organization chart of the persons and groups having specific responsibilities in fire suppression.
fire swatter Equipment Technology Committee ETC Approved A fire tool that consists of a thick, flat piece of rubber on a long handle used to drag over or smother out flames of grass fires.
fire tool cache Equipment Technology Committee ETC Approved A supply of fire tools and equipment assembled in planned quantities or standard units at a strategic point for exclusive use in wildland operations.
fire trap (material accumulation) Fire Weather Subcommittee FWS Approved An accumulation of highly combustible material, rendering firefighting dangerous.
fire trap (situational) Fire Weather Subcommittee FWS Approved Any situation in which it is highly dangerous to fight fire.
fire treatment Fire Use Subcommittee FUSC Approved The use of fire to accomplish a specified objective.
fire triangle Fire Behavior Subcommittee FBSC Approved Instructional aid in which the sides of a triangle are used to represent the three factors (oxygen, heat, fuel) necessary for combustion and flame production; removal of any of the three factors causes flame production to cease.
fire type FMB Fire Management Board Approved A management distinction, made to satisfy legal and budget constraints, based on whether the ignition source was planned or unplanned. Under the implementation guidance, only two types of wildland fire - wildfire and prescribed fire - are recognized.
fire vector Wildland Fire Investigation Subcommittee WFISC Approved The direction of fire spread identified as one of three categories: advancing, lateral, or backing.
fire weather Fire Weather Subcommittee FWS Approved Weather conditions which influence fire ignition, behavior, and suppression.
fire weather forecast Fire Weather Subcommittee FWS Approved A weather prediction specially prepared for use in wildland fire operations and prescribed fire.
Fire Weather Index (FWI) FDSC Fire Danger Subcommittee Approved A numerical rating in the Canadian fire danger rating system, based on meteorological measurements of fire intensity in a standard fuel type. (The standard fuel type is representative of jack pine and lodgepole pine.) The FWI is comprised of three fuel moisture codes, covering classes of forest fuel of different drying rates, and two indices that represent rate of spread and the amount of available fuel. 
fire weather station Fire Weather Subcommittee FWS Approved A meteorological station specially equipped to measure weather elements that have an important effect on fire behavior.
fire weather watch Fire Weather Subcommittee FWS Approved A Fire Weather Watch is issued to advise of conditions which could result in extensive wildland fire occurrence or extreme fire behavior, which are expected to develop in the next 12 to 48 hours, but not more than 72 hours. In cases of dry lightning, a Fire Weather Watch may be issued for the next 12 hours. 
fire whirl Fire Weather Subcommittee FWS Approved Spinning vortex column of ascending hot air and gases rising from a fire and carrying aloft smoke, debris, and flame. Fire whirls range in size from less than one foot to over 500 feet in diameter. Large fire whirls have the intensity of a small tornado.
Fire Year Approved Calendar year in which the fire started
fire-day FDSC Fire Danger Subcommittee Approved Standard 24-hour period beginning at 1000 hours, during which most wildfires undergo a predictable speeding up and slowing down of intensity, depending primarily on the influence of weather and fuel factors.
fire-flood cycle Fire Weather Subcommittee FWS Approved The greatly increased rate of water run off and soil movement from steep slopes that may follow removal of the vegetative cover by burning.
fire-proofing IOSC Incident Operations Subcommittee Approved Removal or treatment of fuels to reduce the danger of fires igniting or spreading. (E.g., fire-proofing roadsides, campsites, structural timber.) Protection is relative, not absolute.
firearms and explosives use Communication, Education, and Prevention Committee CEPC In Development
firebrand Fire Behavior Subcommittee FBSC Approved Any source of heat, natural or human made, capable of igniting wildland fuels. Flaming or glowing fuel particles that can be carried naturally by wind, convection currents, or by gravity into unburned fuels.
firebreak IOSC Incident Operations Subcommittee Approved A natural or constructed barrier used to stop or check fires that may occur, or to provide a control line from which to work.
FIRECAST Fire Weather Subcommittee FWS Approved Set of computerized FIREMODELS run during fire season at the operations coordination center on preselected locations to indicate possible fire spread from those points for that date.
FireCode Incident Business Committee IBC Approved A standardized code used by the federal wildland fire agencies/bureau assigned to effectively track and compile cost information for emergency suppression expenditures. The FireCode is incorporated into each agency’s accounting code structure.
firefighter IOSC Incident Operations Subcommittee Archived Person whose principal function is fire suppression.
firefighting forces IOSC Incident Operations Subcommittee Approved Qualified firefighters, together with their equipment and material, used to suppress wildland fires.
fireground Wildland Fire Investigation Subcommittee WFISC Approved Operational area on which firefighters combat a fire.
Firelamp (Fire and Land Management Planning) Fire Use Subcommittee FUSC Approved Computerized multi-resource model that simulates the effects that naturally caused prescribed fires have on the future production of natural resources such as timber, forage, wildlife, recreation, and water.
fireline (administration) Incident Business Committee IBC Approved For purposes of pay administration for hazardous duty, a fireline is defined as the area within or adjacent to the perimeter of an uncontrolled wildfire of any size in which action is being taken to control fire. Such action includes operations, which directly support control of fire (e.g. activities to extinguish the fire, ground scouting, spot fire patrolling, search and rescue operations, and backfiring).
fireline (line) IOSC Incident Operations Subcommittee Approved The part of a containment or control line that is scraped or dug to mineral soil.
Fireline Explosives (FLE) Equipment Technology Committee ETC Approved Specially developed coils containing explosive powder that are detonated to create a fireline through ground fuels.
fireline intensity (heat release) Fire Behavior Subcommittee FBSC Approved The product of the available heat of combustion per unit of ground and the rate of spread of the fire, interpreted as the heat released per unit of time for each unit length of fire edge. The primary unit is Btu per second per foot (Btu/sec/ft) of fire front.
fireline intensity (rate) Fire Behavior Subcommittee FBSC Approved The rate of heat release per unit time per unit length of fire front. Numerically, it is the product of the heat yield, the quantity of fuel consumed in the fire front, and the rate of spread.
FIRESCOPE IOSC Incident Operations Subcommittee Archived Firefighting Resources of California Organized for Potential Emergencies. A multi-agency coordination system designed to improve the capabilities of California's wildland fire protection agencies. Its purpose is to provide more efficient resources allocation and utilization, particularly in multiple or large fire situations during critical burning conditions. 
firesetter Wildland Fire Investigation Subcommittee WFISC Approved Person who starts a fire, usually deliberately and maliciously.
firesetting Wildland Fire Investigation Subcommittee WFISC Approved Starting a fire, usually deliberately and maliciously.
fireworks Communication, Education, and Prevention Committee CEPC In Development Any composition or device designed to produce a visible or audible effect by  combustion, deflagration, or detonation, and which meets the defintion of "consumer fireworks"  or "display fireworks" as defined in 27 CFR 555.11.
firing out IOSC Incident Operations Subcommittee Approved The act of setting fire to unburned fuels located between the control line and main fire in burning out operations.
firing technique IOSC Incident Operations Subcommittee Approved Any method or pattern of igniting a wildland area to consume the fuel in a prescribed pattern. E.g., heading or backing fire, spot fire, strip-head fire, and ring fire.
first aid Incident Business Committee IBC Approved Emergency care or treatment given to an ill or injured person before regular medical care can be obtained. First aid is generally provided by someone other than a physician. On incidents, most first aid is provided in the field or camp by medical unit personnel such as Emergency Medical Technicians (EMT).
first fuel ignited Wildland Fire Investigation Subcommittee WFISC Approved The first combustible material ignited beyond the components of the ignition source itself.
first name Data Management Committee DMC Approved The first name of the resource as it appears on a government issued ID.
First Order Fire Effects (FOFE) Fire Use Subcommittee FUSC Approved The effects that concern the direct or immediate consequences of fire, such as biomass consumption, crown scorch, bole damage, and smoke production. First order effects form an important basis for predicting secondary effects such as tree regeneration, plant succession, and changes in site productivity, but these involve interaction with many other non-fire variables. 
first-degree burn Risk Management Committee RMC Approved A burn which causes only pain, redness, and swelling.
first-in Wildland Fire Investigation Subcommittee WFISC Approved Firefighters initially attacking a fire, usually the first to arrive at the fire scene.
fitness level Incident and Position Standards Committee IPSC Approved A descriptor of a human resource's physical work capacity
fix Geospatial Subcommittee GSC Approved Geographical position determined by visual reference to the surface, by reference to one or more radio navigational aids, by celestial plotting, or by any other navigational device.
fixed tank National Interagency Aviation Committee NIAC Approved A device mounted inside or directly underneath an aircraft which can contain water or retardant for dropping onto a fire.
flame (light) Fire Behavior Subcommittee FBSC Approved Light given off by burning gasses during the combustion process.
flame (scientific) Fire Behavior Subcommittee FBSC Approved A mass of gas undergoing rapid combustion, generally accompanied by evolution of sensible heat and incandescence.
flame angle Fire Behavior Subcommittee FBSC Approved Angle between the flame at the leading edge of the fire front and the ground surface, expressed in degrees.
flame depth Fire Behavior Subcommittee FBSC Approved The depth of the fire front.
flame height Fire Behavior Subcommittee FBSC Approved The average maximum vertical extension of flames at the leading edge of the fire front. Occasional flashes that rise above the general level of flames are not considered. This distance is less than the flame length if flames are tilted due to wind or slope. 
flame length Fire Behavior Subcommittee FBSC Approved The distance between the flame tip and the midpoint of the flame depth at the base of the flame (generally the ground surface), an indicator of fire intensity.
flame thrower Equipment Technology Committee ETC Approved Device for throwing a stream of flaming liquid, used to facilitate rapid ignition during burn out operations on a wildfire or during a prescribed fire operation.
flaming combustion phase Fire Use Subcommittee FUSC Approved Luminous oxidation of gases evolved from the rapid decomposition of fuel. This phase follows the pre-ignition phase and precedes the smoldering combustion phase, which has a much slower combustion rate. Water vapor, soot, and tar comprise the visible smoke. Relatively efficient combustion produces minimal soot and tar, resulting in white smoke; high moisture content also produces white smoke. 
flaming front Fire Behavior Subcommittee FBSC Approved That zone of a moving fire where the combustion is primarily flaming. Behind this flaming zone combustion is primarily glowing or involves the burning out of larger fuels (greater than about 3 inches in diameter). Light fuels typically have a shallow flaming front, whereas heavy fuels have a deeper front.
flaming phase Fire Behavior Subcommittee FBSC Approved That phase of a fire where the fuel is ignited and consumed by flaming combustion.
flammability Fire Behavior Subcommittee FBSC Approved The relative ease with which fuels ignite and burn regardless of the quantity of the fuels. Preferred to "inflammability."
flammable Wildland Fire Investigation Subcommittee WFISC Approved Easily ignitable and capable of burning and producing flames.
flammable gas, oil, and other liquids conditions (event) National Coordination System Committee NCSC Approved An event dealing with the various situations that arise as a result of the presence of flammable gas and liquids such as gasoline, oil, etc.
flammable liquid Wildland Fire Investigation Subcommittee WFISC Approved A liquid generally with a flash point below 140F (60C) and a vapor pressure that does not exceed 40 PSI at 100F (37.8C).
flank fire IOSC Incident Operations Subcommittee Approved A firing technique consisting of treating an area with lines of fire set into the wind which burn outward at right angles to the wind.
flanking fire suppression IOSC Incident Operations Subcommittee Approved Attacking a fire by working along the flanks either simultaneously or successively from a less active or anchor point and endeavoring to connect two lines at the head.
flanks of a fire (fire spread) Fire Environment Committee FENC Approved The parts of a fire’s perimeter that are roughly parallel to the main direction of fire spread.
flanks of a fire (spread) Fire Environment Committee FENC, Wildland Fire Investigation Subcommittee WFISC Approved The parts of a fire's perimeter that are roughly parallel to the main direction of spread.
flapper Equipment Technology Committee ETC Approved Fire suppression tool, sometimes improvised, used in direct attack for smothering out flames along a fire edge; may consist merely of a green pine bough or wet sacking, or be a manufactured tool such as a flap of belting fabric fastened to a long handle.
flare-up IOSC Incident Operations Subcommittee, Fire Environment Committee FENC Approved Any sudden acceleration in rate of spread or intensification of the fire. Unlike blowup, a flare-up is of relatively short duration and does not radically change existing control plans.
flares/fusees Communication, Education, and Prevention Committee CEPC In Development
flash fuels Fire Weather Subcommittee FWS Approved Highly combustible fine fuels such as grass, leaves, draped pine needles, fern, tree moss and some kinds of slash, which ignite readily and are consumed rapidly when dry.
flash point Wildland Fire Investigation Subcommittee WFISC Approved Lowest temperature at which the vapor of a combustible liquid can be made to ignite in air.
flashover (behavior) Fire Weather Subcommittee FWS Approved Rapid combustion and/or explosion of unburned gases trapped at some distance from the main fire front. Usually occurs only in poorly ventilated topography.
flashover (stage of fire) Fire Weather Subcommittee FWS Approved Stage of a fire at which all surfaces and objects within a space have been heated to their ignition temperature, and flame breaks out almost at once over the surface of all objects within the space.
flight crew member National Interagency Aviation Committee NIAC Approved An individual holding a valid Federal Aviation Administration (FAA) Airman’s Certificate and flight physical as a prerequisite to performance of the duties of the position during flight: e.g., Pilot, co-Pilot, flight engineer, or flight navigator.
flight following National Interagency Aviation Committee NIAC Approved The method and process through which an aircraft is tracked from departure point to destination. Flight following is the knowledge of the aircraft location and condition at regular intervals with a reasonable degree of certainty such that, in the event of mishap, those on board may be rescued. 
flight path (intended) National Interagency Aviation Committee NIAC Approved Specified information relating to the intended flight of an aircraft that is filed orally or in writing with an air traffic control facility.
flight path (tracking) National Interagency Aviation Committee NIAC Approved Track of an aircraft over the earth's surface.
flight time National Interagency Aviation Committee NIAC Approved The time from the moment the aircraft first moves under its own power for the purpose of flight until the moment it comes to rest at the next point of landing.
flight visibility National Interagency Aviation Committee NIAC Approved Average forward horizontal distance from the cockpit of an aircraft in flight at which prominent unlighted objects may be seen and identified by day and prominent lighted objects may be seen and identified by night.
flint/friction Communication, Education, and Prevention Committee CEPC In Development
floatable pump Equipment Technology Committee ETC Approved Small portable pump that floats in the water source.
flooding (event) National Coordination System Committee NCSC Approved An event dealing with response to a major flood.
flow conditioner Equipment Technology Committee ETC Approved Chemical powders that will, in very small quantities, tend to prevent other powders from caking and flocculating. Imparts free-flowing qualities to powder. Used with fire retardant chemicals.
fluid foam Equipment Technology Committee ETC Approved A low expansion foam type with some bubble structure and moderate drain time, exhibiting properties of both wet and dry foam types, which is used for extinguishment, protection, and mopup.
fly ash Fire Use Subcommittee FUSC Approved Particulate matter emitted by a fire and larger than 10 microns in diameter with a consequently short residence time in the atmosphere.
foam Equipment Technology Committee ETC Approved The aerated solution created by forcing air into, or entraining air in water containing a foam concentrate by means of suitably designed equipment or by cascading it through the air at a high velocity. Foam reduces combustion by cooling, moistening and excluding oxygen. 
foam blanket Equipment Technology Committee ETC Approved A layer of foam which forms an insulating and reflective barrier to heat and is used for fuel protection, suppression, and mopup.
foam concentrate Equipment Technology Committee ETC Approved The concentrated foaming agent as received from the manufacturer which, when added to water, creates a foam solution; use only those approved for use in wildland fire situations by the authority having jurisdiction.
foam generation Equipment Technology Committee ETC Approved The foam production process of forcing air into or entraining air in foam solution, creating a mass of bubbles.
foam line IOSC Incident Operations Subcommittee Approved A body of foam placed along areas to be protected from fire; also used as an anchor for indirect attack in place of hand-made fire line.
foam solution Equipment Technology Committee ETC Approved A low expansion foam type with no expansion, therefore lacking bubble structure, which is used for mopup and flame knock down.
foam systems Equipment Technology Committee ETC Approved The apparatus and techniques used to mix concentrate with water to make solution, pump and mix air and solution to make foam, and transport and apply foam. (Systems defined here include compressed air foam and nozzle aspirated.)
foam type Equipment Technology Committee ETC Approved A term used to describe the consistency and viscosity of low expansion foam as the combination of drain time and expansion.
foaming agent Equipment Technology Committee ETC Approved An additive that reduces the surface tension of water (producing wet water) causing it to spread and penetrate more effectively and which produces foam through mechanical means.
Foehn wind Fire Weather Subcommittee FWS Approved A warm, dry and strong general wind that flows down into the valleys when stable, high pressure air is forced across and then down the lee slopes of a mountain range. The descending air is warmed and dried due to adiabatic compression producing critical fire weather conditions. Locally called by various names such as Santa Ana winds, Devil winds, North winds, Mono winds, etc. 
folding tank Equipment Technology Committee ETC Approved A portable, collapsible water tank with a tubular frame. Tank capacities vary in size from 500-1500 gallons.
Food Unit National Incident Management System Integration Committee NIMSIC Approved Food Unit staff determine the food and hydration needs of personnel assigned to the incident and plan menus, order food, provide cooking facilities, cook and serve food, maintain food service areas, and manage food security and safety.Efficient food service is especially important for extended incidents. Food Unit staff anticipate incident needs, such as the number of people who will need to be fed and whether the incident’s type, location, or complexity predicates special food needs. The unit staff supply food to meet the nutritional needs during the entire incident, including all remote locations (e.g., camps and staging areas), and supply on-site food service to operations personnel who are unable to leave their assignments. Careful planning and monitoring helps ensure food safety before and during food service operations, including the assignment, as needed, of public health professionals with expertise in environmental health and food safety.
forb Fire Use Subcommittee FUSC Approved A plant with an herbaceous (soft, rather than permanent woody) stem, that is not a grass or grasslike plant.
forced landing National Interagency Aviation Committee NIAC Approved Landing necessitated by failure of engines, systems, or components which makes continued flight impossible and which may not result in damage.
forcible entry Wildland Fire Investigation Subcommittee WFISC Approved Entering a structure of vehicle illegally by means or physical force, often characterized by prying doors and breaking windows.
forecast area Fire Weather Subcommittee FWS Approved Geographical area for which a fire weather forecast is specified.
foreign incident (event) National Coordination System Committee NCSC Approved An event dealing with a wildland fire originating from a country outside of the U.S., which has burned onto U.S. soil.
forest fire IOSC Incident Operations Subcommittee Archived Variously defined for legal purposes (e.g., the State of California Public Resources Code: uncontrolled fire on lands covered wholly or in part by timber, brush, grass, grain, or other flammable vegetation). Types of fires are ground, surface, and crown.
forest protection IOSC Incident Operations Subcommittee Archived Forestry branch concerned with prevention and damage control to forests from human actions (unauthorized fire, grazing, felling, smoke), pests and pathogens, and damage from storm, frost, and other climatic agents.
forest residue Fire Use Subcommittee FUSC Approved Accumulation in the forest of living or dead (mostly woody) material that is added to and rearranged by human activities such as harvest, cultural operations, and land clearing.
Forest Service assisted indicator Incident Business Committee IBC Approved Indicates if the Forest Service provided assistance on an incident outside their jurisdiction.
Forest Service job code Incident Business Committee IBC Approved A code used to indicate the Forest Service job accounting code for the incident. This is specific to the Forest Service and is usually displayed as two-character prefix on the FireCode.
Forest Service override code Incident Business Committee IBC Approved A code used to indicate the Forest Service override code for the incident. This is specific to the Forest Service, and is usually displayed as a four-character suffix on FireCode.
Forward Looking Infrared (FLIR) National Interagency Aviation Committee NIAC Approved Hand held or aircraft mounted device designed to detect heat differentials and display their images on a video screen. FLIRs have thermal resolution similar to IR line scanners, but their spatial resolution is substantially less; commonly used to detect hotspots and flareups obscured by smoke, evaluate the effectiveness of firing operations, or detect areas needing mopup. 
forward rate of spread IOSC Incident Operations Subcommittee Approved The speed with which a fire moves in a horizontal direction across the landscape, usually expressed in chains per hour or feet per minute.
fragile fire cause objects Wildland Fire Investigation Subcommittee WFISC Approved Objects that are easily susceptible to damage from head and flame and can be easily damaged or destroyed by suppression action and/or during the evidence collection process. E.g., cigarette ash.
free burning Fire Behavior Subcommittee FBSC Approved The condition of a fire or part of a fire that has not been slowed by natural barriers or by control measures.
free drop National Interagency Aviation Committee NIAC Approved Cargo, not attached to a parachute, that is dropped intentionally from an aircraft in flight.
free flow (hydraulics) Equipment Technology Committee ETC Approved Maximum water flow rate a fire pump will attain when there are no restrictions at the pump outlet or losses due to friction or head.
freezing rain Fire Weather Subcommittee FWS Approved Rain that freezes upon contact with objects on the ground.
frequency identifier Approved Code used to ease identification of a zone.
frequency of occurrence IOSC Incident Operations Subcommittee Archived A quantitative expression of the presence or absence of individuals of a species in a population; the ratio between the number of sample units that contain a species and the total number of sample units.
frequency use designator RSUSC Wildland Fire Radio Standards and Use Committee Approved A designation of the kind of communications that will occur on an assigned radio frequency.
friction layer Fire Weather Subcommittee FWS Approved The layer of the atmosphere in which the frictional force of the earth's surface exercises an appreciable influence on winds.
friction loss Equipment Technology Committee ETC Approved Pressure loss caused by the movement of water or solution against the interior surface of fire hose, pipe, or fittings; normally measured in pressure loss per length of hose or pipe.
Friction Reducing Agent (FRA) Equipment Technology Committee ETC Approved Water soluble substance that reduces frictional drag of solutions and dampens turbulent flow while being pumped through pipe or hose.
front Fire Weather Subcommittee FWS Approved In meteorology, the boundary between two air masses of differing atmospheric properties.
frost Fire Weather Subcommittee FWS Approved Crystals of ice formed and deposited like dew, but at a temperature below freezing.
frozen FDSC Fire Danger Subcommittee Approved In the 1978 version of NFDRS, the herbaceous stage when cold temperatures kill herbaceous plants and force woody fuels into dormancy.
fuel Fire Use Subcommittee FUSC Approved Any combustible material, especially petroleum-based products and wildland fuels.
fuel arrangement Fire Use Subcommittee FUSC Approved A general term referring to the spatial distribution and orientation of fuel particles or pieces.
fuel bed Fire Use Subcommittee FUSC Approved An array of fuels usually constructed with specific loading, depth, and particle size to meet experimental requirements; also, commonly used to describe the fuel composition.
fuel bed depth Fire Use Subcommittee FUSC Approved Average height of surface fuels contained in the combustion zone of a spreading fire front.
fuel break Fire Use Subcommittee FUSC Approved A natural or manmade change in fuel characteristics which affects fire behavior so that fires burning into them can be more readily controlled.
fuel break system Fire Use Subcommittee FUSC Approved A series of modified strips or blocks tied together to form continuous strategically located fuel breaks around land units.
fuel characteristics Fire Use Subcommittee FUSC Approved Factors that make up fuels such as compactness, loading, horizontal continuity, vertical arrangement, chemical content, size and shape, and moisture content.
fuel class FDSC Fire Danger Subcommittee Approved Group of fuels possessing common characteristics. Dead fuels are grouped according to 1-, 10-, 100-, and 1000-hour timelag, and living fuels are grouped as herbaceous (annual or perennial) or woody.
fuel condition Fire Use Subcommittee FUSC Approved Relative flammability of fuel as determined by fuel type and environmental conditions.
fuel continuity Fire Use Subcommittee FUSC Approved The degree or extent of continuous or uninterrupted distribution of fuel particles in a fuel bed thus affecting a fire's ability to sustain combustion and spread. This applies to aerial fuels as well as surface fuels.
fuel depth Fire Use Subcommittee FUSC Approved The average distance from the bottom of the litter layer to the top of the layer of fuel, usually the surface fuel.
Fuel Dryness Level (DL) Fire Weather Subcommittee FWS Approved A quantitative measure of fuel moisture and receptability to ignition as determined by an accepted Fire Danger Rating System index that influences fire growth, intensity, or activity.
fuel group Fire Use Subcommittee FUSC Approved An identifiable association of fuel elements of distinctive species, form, size, arrangement, or other characteristics. General fuel groups are grass, brush, timber, and slash.
fuel loading FDSC Fire Danger Subcommittee, Fire Use Subcommittee FUSC Approved The amount of fuel present expressed quantitatively in terms of weight of fuel per unit area. This may be available fuel (consumable fuel) or total fuel and is usually dry weight.
fuel management Fire Use Subcommittee FUSC Approved Act or practice of controlling flammability and reducing resistance to control of wildland fuels through mechanical, chemical, biological, or manual means, or by fire, in support of land management objectives.
fuel model FDSC Fire Danger Subcommittee Approved Simulated fuel complex for which all fuel descriptors required for the solution of a mathematical rate of spread model have been specified.
fuel modification Fire Use Subcommittee FUSC Approved Manipulation or removal of fuels to reduce the likelihood of ignition and/or to lessen potential damage and resistance to control (e.g., lopping, chipping, crushing, piling and burning).
fuel moisture analog Fire Behavior Subcommittee FBSC Approved Device that emulates the moisture response of specific classes of dead fuels, constructed from organic or inorganic materials (e.g., half-inch ponderosa pine dowels representing ten-hour timelag fuels).
fuel moisture content Fire Behavior Subcommittee FBSC Approved The quantity of moisture in fuel expressed as a percentage of the weight when thoroughly dried at 212 degrees F.
fuel moisture indicator stick Fire Behavior Subcommittee FBSC Approved A specially prepared stick or set of sticks of known dry weight continuously exposed to the weather and periodically weighed to determine changes in moisture content as an indication of moisture changes in wildland fuels.
fuel reduction Fire Use Subcommittee FUSC Approved Manipulation, including combustion, or removal of fuels to reduce the likelihood of ignition and/or to lessen potential damage and resistance to control.
fuel size class Fire Behavior Subcommittee FBSC Approved A category used to describe the diameter of down dead woody fuels. Fuels within the same size class are assumed to have similar wetting and drying properties, and to preheat and ignite at similar rates during the combustion process.
fuel temperature FDSC Fire Danger Subcommittee Approved The temperature reading measured from a fuel stick fully exposed to sunlight, above a representative fuel bed, using one of two methods (within a 3/4-inch or across a 1/2-inch pine dowel).
fuel tender Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Any vehicle capable of supplying engine fuel to ground or airborne equipment.
fuel treatment Fire Use Subcommittee FUSC Approved Manipulation or removal of fuels to reduce the likelihood of ignition and/or to lessen potential damage and resistance to control (e.g., lopping, chipping, crushing, piling and burning).
fuel type Fire Use Subcommittee FUSC Approved An identifiable association of fuel elements of distinctive species, form, size, arrangement, or other characteristics that will cause a predictable rate of spread or resistance to control under specified weather conditions.
fuels treatment polygon In Development A polygon representing the area(s) of unique fuels treatments during a single timeframe.
fuels wet flag FDSC Fire Danger Subcommittee Approved A one-character code indicating whether or not fine fuels are wet or dry.
fugitive color SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved A coloring agent used in fire retardants that is designed to fade rapidly following retardant application in order to minimize the visual impacts of the retardant.
fulfillment comment IOSC Incident Operations Subcommittee Approved Communication about the request and fulfilling that request
fulfillment status IOSC Incident Operations Subcommittee Approved Indicates the state of the request.
full-thickness burn Risk Management Committee RMC Approved A burn involving all the layer of the skin. Muscle layers below the skin and bones may also be damaged. Areas of the skin may be charred black or areas that are dry and white.
fume Risk Management Committee RMC, Fire Use Subcommittee FUSC Approved An airborne irritating, noxious, or toxic smoke, vapor, or any combination of these produced by a volatile substance or a chemical reaction.
function National Incident Management System Integration Committee NIMSIC Approved In ICS, function refers to the five major activities: command, operations, planning, logistics and finance/administration.
fusee Equipment Technology Committee ETC Approved A colored flare designed as a railway warning device, widely used to ignite backfires and other prescribed fires.
Gallons per Minute (GPM) Equipment Technology Committee ETC Approved The measure of water flow in firefighting. It is used to measure the output of wildland and structural fire engines, pumps, hose streams, nozzles, hydrants, and water mains.
gap IASS Interagency Aerial Supervision Subcommittee Approved Weak or missed area in a retardant drop or in a fireline.
gas cooking/warming/lighting device Communication, Education, and Prevention Committee CEPC In Development
gate valve Equipment Technology Committee ETC Approved A valve with a gate-like disk that moves up and down at right angles to the flow when actuated by a stem screw and hand wheel. Gate valves are best for service that requires infrequent valve operation and where the disk is kept either fully open or closed. 
gear pump Equipment Technology Committee ETC Approved Positive displacement pump which uses closely meshed gears to propel water when high pressures and low volumes are desired; can be used safely only with clear water-- suspended particles of soil or rocks can quickly wear the gears and reduce pressure and volume of water. 
general fire weather forecast Fire Weather Subcommittee FWS Approved A forecast, issued daily during the regular fire season to resource management agencies, that is intended for planning of daily fire management activities, including daily staffing levels, prevention programs, and initial attack on wildfires.
General Origin Area (GOA) Wildland Fire Investigation Subcommittee WFISC Approved The larger area where the fire first established itself and is identified by an analysis of the fire behavior context, macroscale fire pattern indicators, and witness statements.
General Schedule Employee Incident Business Committee IBC Approved A regular federal government employee who is compensated under the General Schedule (GS) Pay Plan.
General Staff National Incident Management System Integration Committee NIMSIC Approved A group of incident personnel organized according to function and reporting to the Incident Commander or Unified Command. The ICS General Staff consists of the Operations Section Chief, Planning Section Chief, Logistics Section Chief, Finance/Administration Section Chief.
general status (resource) Incident and Position Standards Committee IPSC Approved Indicates whether the resource is available or unavailable to fill a capability request.
general winds Fire Weather Subcommittee FWS Approved Large scale winds caused by high- and low-pressure systems but generally influenced and modified in the lower atmosphere by terrain.
geographic area National Coordination System Committee NCSC Approved A boundary designated by governmental agencies (wildland fire protection agencies) within which they work together for the interagency, intergovernmental planning, coordination, and operations leadership for the effective utilization of emergency management resources within their area. There are ten geographic areas. A listing of the areas can be found in the National Interagency Mobilization Guide, Chapter 70 along with listings of the Geographic Coordinating Areas and Geographic Area Coordination Centers.
Geographic Area (GA) code National Coordination System Committee NCSC Approved A code that identifies one of the wildland fire geographic areas.
Geographic Area (GA) name National Coordination System Committee NCSC Approved The name of the geographic area that identifies a boundary designated by wildland fire protection agencies within which they work together for the interagency, intergovernmental planning, coordination, and operations leadership for the effective utilization of emergency management resources.
Geographic Area Coordinating Group (GACG) FMB Fire Management Board Approved An interagency body of fire management representatives from each federal and state land management agency within a nationally recognized regional area that provides leadership and support to facilitate safe and efficient fire management activities. Working collaboratively, a GACG's mission is not only for wildland fire emergencies, but for other emergency incidents, as necessary.
Geographic Area Coordination Center (GACC) National Coordination System Committee NCSC, FMB Fire Management Board Approved The physical location of an interagency, regional operation center for the effective coordination, mobilization and demobilization of emergency management resources. A coordination center serves federal, state and local wildland fire agencies through logistical coordination of resources throughout the geographic area, and with other geographic areas, as well. Listings of geographic coordination centers and their respective geographic coordinating areas can be found within the National Interagency Mobilization Guide. 
Geographic Area Coordination Center (GACC) code National Coordination System Committee NCSC Approved Shortened form of Geographic Area Coordination Center name.
Geographic Area Coordination Center (GACC) name National Coordination System Committee NCSC Approved The name of an interagency operations center that provides coordination, mobilization, and demobilization of emergency management resources within a specific geographic coordinating area.
Geographic Area Coordination Center unit identifier Approved NWCG Unit Identifier for GACC Boundary
geographic coordinating area National Coordination System Committee NCSC Approved A boundary designated by governmental agencies (wildland fire protection agencies), that may coincide with a geographic area boundary or may be a subdivision of a geographic area within which they work together coordinating, for the effective, mobilization and demobilization of emergency management resources within their area. Listings of geographic coordinating areas and geographic coordination centers can be found in the National Interagency Mobilization Guide, Chapter 20, Section 21.1. 
Geographic Coordinating Area (GCA) code National Coordination System Committee NCSC Approved A code representing a wildland fire geographic coordinating area.
Geographic Coordinating Area (GCA) name National Coordination System Committee NCSC Approved The name of the wildland fire geographic coordinating area.
Geographic Information System Acres Approved GIS calculated acres within the fire perimeter, not adjusted for unburned areas
geometry identifier Approved Primary key for linking geospatial objects with other database systems.
Geostationary Operational Environmental Satellite (GOES) FDSC Fire Danger Subcommittee Approved The satellite used for data relay from NFDRS weather stations to ASCADS.
getaway time IOSC Incident Operations Subcommittee Approved Elapsed time from receipt of notification by the personnel charged with initiating suppression action to the departure of the first attack unit.
glass refraction/magnification Communication, Education, and Prevention Committee CEPC Superceded
Global Positioning System (GPS) National Coordination System Committee NCSC Approved A system of navigational satellites operated by the U.S. Department of Defense and available for civilian use. The system can track objects anywhere in the world with an accuracy of approximately 40 feet.
glowing combustion Fire Use Subcommittee FUSC Approved The process of oxidation of solid fuel accompanied by incandesence. All volatiles have already been driven off, oxygen reaches the combustion surfaces, and there is no visible smoke. This phase follows the smoldering combustion phase and continues until the temperature drops below the combustion threshold value, or until only non-combustible ash remains. 
glowing combustion phase Fire Use Subcommittee FUSC Approved The final phase of combustion following flaming and smoldering phases.
going fire IOSC Incident Operations Subcommittee Approved Any wildfire on which suppression action has not reached an extensive mop up stage.
government vehicle Incident Business Committee IBC Approved A vehicle owned by, on loan to, leased or rented by the government.
gradient wind (flow) Fire Weather Subcommittee FWS Approved Wind flowing parallel to pressure isobars or contours with low pressure on the left of the observer in the Northern Hemisphere; velocity such that the pressure gradient, Coriolis, and centrifugal force acting in the area are in balance.
gradient wind (weather system) Fire Weather Subcommittee FWS Approved Wind created by differing barometric pressures between high- and low-pressure systems. Velocity is generally five to 30 miles per hour, and wind shifts are usually gradual as systems move and shift.
Graphic Scale (GS) Incident and Position Standards Committee IPSC Approved A graphic scale is a line marked off on a map which compares map distances to the ground distance in "different" units of measurements.
grass fire Fire Behavior Subcommittee FBSC Approved Any fire in which the predominant fuel is grass or grasslike.
grass type FDSC Fire Danger Subcommittee Approved In NFDRS, the two grass types (annual, perennial) determine how seasonal drying of live herbaceous fuels is modeled.
gravimetric Fire Weather Subcommittee FWS Approved Of, or pertaining to, measurement by weight.
gravity tank Equipment Technology Committee ETC Approved Water storage tank for fire protection and sometimes community water service that supplies water by gravity pressure.
green-up FDSC Fire Danger Subcommittee Approved Green-up for the 1978 version of NFDRS model is defined as the beginning of a new cycle of plant growth. Green-up usually occurs once a year, except in desert areas where rainy periods can produce a flush of new growth more than once a year. Green-up may be signaled at different dates for different fuel models. Green-up should not be started when the first flush of green occurs in the area. Instead, the vegetation that will be the fire problem (represented by the NFDRS fuel model associated with the weather station) when it matures and cures should be identified. Green-up should start when the majority of this vegetation starts to grow. 
greenbelt WMSC WUI Mitigation Subcommittee Archived Landscaped and regularly maintained fuel break, usually put to some additional use (e.g., golf course, park, playground).
greenhouse effect Fire Weather Subcommittee FWS Approved The heating of the earth's surface by both atmospheric infrared radiation and incoming solar radiation.
greenness factor FDSC Fire Danger Subcommittee Approved In the 1988 version of NFDRS, a code scaled from 0 to 20 representing the greenness of grasses and shrubs from near dead to maximum greenness.
grid ignition technique Fire Use Subcommittee FUSC Approved Method of igniting prescribed fires in which ignition points are set individually at predetermined spacing with predetermined timing throughout the area to be burned.
grid search technique Wildland Fire Investigation Subcommittee WFISC Approved A search technique typically dividing into squares the specific origin area and ignition area of a wildland fire to systematically search for microscale fire pattern indicators and evidence.
gridding IOSC Incident Operations Subcommittee Approved To search for a small fire by systematically traveling over an area on parallel courses or gridlines.
Gross Axle Weight Rating (GAWR) Equipment Technology Committee ETC Approved The value specified by the manufacturer as the maximum allowable weight placed on an axle of a vehicle when fully equipped, including payload, fluids and occupants.
Gross Vehicle Weight (GVW) Equipment Technology Committee ETC Approved Actual vehicle weight, including chassis, body, cab, equipment, water, fuel, crew, and all other load.
Gross Vehicle Weight Rating (GVWR) Equipment Technology Committee ETC Approved The value specified by the manufacturer as the maximum allowable weight of a vehicle fully equipped, including payload, fluids and occupants.
gross weight National Interagency Aviation Committee NIAC Approved Total allowable weight of a loaded aircraft for takeoff or landing, adjusted for altitude differences.
ground effect National Interagency Aviation Committee NIAC Approved Reaction of a rotor downdraft against the ground surface, forming a "ground cushion" that increases lifting capability of that section of air.
ground fire Fire Use Subcommittee FUSC Approved Fire that consumes the organic material beneath the surface litter ground, such as a peat fire.
ground fireworks Communication, Education, and Prevention Committee CEPC In Development Emit flame and sparks which when set off adjacent to flammable vegetation can easily ignite a fire. . 
ground fog Fire Weather Subcommittee FWS Approved Fog which extends vertically to less than 20 feet.
ground fuel Fire Use Subcommittee FUSC Approved All combustible materials below the surface litter, including duff, tree or shrub roots, punky wood, peat, and sawdust, that normally support a glowing combustion without flame.
ground speed National Interagency Aviation Committee NIAC Approved Speed with which an aircraft traverses the ground over which it flies.
Ground Support Unit National Incident Management System Integration Committee NIMSIC Approved Ground Support Unit staff provide ground transportation in support of incident operations. They maintain and repair vehicles and mobile ground support equipment and perform pre- and postuse inspections on all ground equipment assigned to the incident. The staff supply fuel for incident mobile equipment, and develop and implement the incident Traffic Plan. Additionally, during major incidents, Ground Support Unit staff maintain a transportation pool of vehicles (e.g., cars, buses, pickup trucks) suitable for transporting personnel, as opposed to tactical vehicles such as ambulances. Ground Support Unit staff also provide information to the Resources Unit on the location and status of vehicles assigned to the Ground Support Unit.
ground truth Fire Weather Subcommittee FWS Approved Verification at the site of what has been observed and/or measured from aircraft, satellites, other aerial platforms, aerial photographs, or maps.
ground visibility Fire Weather Subcommittee FWS Approved Horizontal visibility observed at the ground.
Group National Incident Management System Integration Committee NIMSIC Approved An organizational subdivision established to divide the incident management structure into functional areas of operation. Groups are composed of resources assembled to perform a special function not necessarily within a single geographic area.
growing season burning Fire Use Subcommittee FUSC Approved Prescribed burning or use of wildland fire during the photosynthetically-active growing season, where live fuel moistures are relatively high and the dominant vegetation, grasses, forbs, and herbaceous vegetation are fully greened.
guard unit IOSC Incident Operations Subcommittee Archived Geographic subdivision of a fire-protected area, delimiting the initial attack bounds of a single fire guard or fire crew.
Gum Thickened Sulphate (GTS) Equipment Technology Committee ETC Approved A dry chemical product which is mixed with water to form a fire retardant slurry.
gust Fire Weather Subcommittee FWS Approved Rapid fluctuations in wind speed with a variation of 10 knots (11.5 mph) or more between peaks and lulls.
hachures (topographic) Incident and Position Standards Committee IPSC Approved A series of short, nearly parallel lines used in map making to represent a sloping surface. Representing a depression or pit, the contour line is joined forming a circle with the hachures on the inside of the circle.
Haines Index Fire Weather Subcommittee FWS Approved An atmospheric index used to indicate the potential for wildfire growth by measuring the stability and dryness of the air over a fire.
hand crew IOSC Incident Operations Subcommittee Approved A number of individuals that have been organized and trained and are supervised principally for operational assignments on an incident.
hand pile/slash Communication, Education, and Prevention Committee CEPC, Fire Use Subcommittee FUSC In Development Made by hand treatment of slash to reduce fire hazard or for other purposes.
handline IOSC Incident Operations Subcommittee Approved Fireline constructed with hand tools.
hangup (tree falling) Hazard Tree and Felling Subcommittee HTTFS Approved A situation in which a tree is lodged in another, preventing it from falling to the ground.
hard suction hose Equipment Technology Committee ETC Approved Noncollapsible suction hose attached to a pump and used to draft water from a source lower than the pump. Customary hose sizes in wildland fire engines are 2 and 2-1/2 inches in diameter (51 and 64 mm).
hazard National Incident Management System Integration Committee NIMSIC Approved Any real or potential condition that can cause injury, illness or death of personnel, or damage to, or loss of equipment or property. The root cause of an unwanted outcome.
hazard assessment Risk Management Committee RMC Approved Assess hazards to determine risks. Assess the impact of each hazard in terms of potential loss, cost, or strategic degradation based on probability and severity.
hazard fuel Fire Use Subcommittee FUSC Approved A fuel complex defined by kind, arrangement, volume, condition, and location that presents a threat of ignition and resistance to control.
hazard map IASC Interagency Airspace Subcommittee Approved Map of the area of operations that shows all of the known aerial hazards, including but not limited to power lines, military training areas, hang gliding areas, etc.
hazard pay Incident Business Committee IBC Approved A salary differential that compensates employees for exposure to hazards in the course of their duties.
hazard reduction Fire Use Subcommittee FUSC Approved Any treatment of living and dead fuels that reduces the potential spread or consequences of fire.
hazardous areas Fire Use Subcommittee FUSC Approved Those wildland areas where the combination of vegetation, topography, weather, and the threat of fire to life and property create difficult and dangerous problems.
hazardous conditions (event) National Coordination System Committee NCSC Approved An event, usually managed by organizations external to the fire community, for which the primary focus is for dealing with a hazardous situation that poses an unreasonable risk to health, safety, and property.
hazardous materials (regulated) Equipment Technology Committee ETC Approved Substances that are identified, classified, and regulated in the Code of Federal Regulations, Title 49 and Hazardous Materials Regulations 175.
hazardous materials (transported) Equipment Technology Committee ETC Approved A substance or material which has been determined by the Secretary of Transportation to be capable of posing an unreasonable risk to health, safety, and property when transported in commerce and which has been so designated.
hazards (water source) Approved A potential source of harm when accessing and using a water source.
haze Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved A sufficient concentration of atmospheric aerosols to affect a visible attenuation of light and measurable reduction in visual range. The aerosol particle diameter is near the wavelength of visible light, optimizing the light scattering efficiency of the particles. 
haze meter Fire Use Subcommittee FUSC Approved Instrument for measuring the dependable range of distance at which a standard smoke column can be detected by the unaided eye under existing haze conditions.
head fire Fire Behavior Subcommittee FBSC Approved A fire spreading or set to spread with the wind.
head of the fire Wildland Fire Investigation Subcommittee WFISC Approved The most rapidly spreading portions of a fire’s perimeter, usually progressing with the wind, up slope, or a combination of the two.
head pressure Equipment Technology Committee ETC Approved Pressure due to elevation of water. Equals 0.433 pounds per square inch (PSI) per foot of elevation. (Approximately 0.5 PSI is required to lift water 1 foot in elevation)
heading National Interagency Aviation Committee NIAC Approved The compass direction in which the longitudinal axis of the aircraft points.
headlamp Equipment Technology Committee ETC Approved Flashlight, ordinarily worn by firefighter on the front of the helmet.
heat Wildland Fire Investigation Subcommittee WFISC Approved Temperatures higher than that of the normal atmosphere, produced by the process of burning or oxidation.
heat content Fire Behavior Subcommittee FBSC Approved The net amount of heat that would be given off if fuel burns when it is absolutely dry, noted as Btu per pound of fuel.
heat low Fire Weather Subcommittee FWS Approved An area of low pressure caused by intense heating of the earth's surface. High surface temperature causes air to expand and rise, resulting in low atmospheric pressure and induces a weak inflow of air at the surface. Air which rises in a heat low is very dry so clouds seldom form. Rising air above a heat low produces a warm upper level high and results in a net outflow of air aloft. Heat lows remain practically stationary over areas which produce them. 
heat of combustion Fire Behavior Subcommittee FBSC Approved The heat energy resulting from the complete combustion of a fuel, expressed as the quantity of heat per unit weight of fuel. The high heat of combustion is the potential available, and the low heat of combustion is the high heat of combustion minus several losses that occur in an open system (primarily heat of vaporization of moisture in the fuel).
heat per unit area Fire Behavior Subcommittee FBSC Approved Total amount of heat released per unit area as the flaming front of the fire passes, expressed as Btu/square foot; a measure of the total amount of heat released in flames.
heat probe Equipment Technology Committee ETC Approved Apparatus used to detect heat.
heat release rate (consumed) Fire Weather Subcommittee FWS Approved Total amount of heat produced per unit mass of fuel consumed per unit time.
heat release rate (released) Fire Weather Subcommittee FWS Approved Amount of heat released to the atmosphere from the convective-lift fire phase of a fire per unit time.
heat transfer Fire Weather Subcommittee FWS Approved Process by which heat is imparted from one body to another, through conduction, convection, and radiation.
Heat Trough Fire Weather Subcommittee FWS Approved A Heat Low which is elongated in shape.
heat value Fire Weather Subcommittee FWS Approved The total heat energy released during combustion, usually published as units of heat energy produced per unit mass of ovendry fuel consumed.
heat yield Fire Weather Subcommittee FWS Approved The heat of combustion corrected for various heat losses, mainly the presence of moisture in the fuel. To a very close approximation, the quantity of heat per pound of fuel burned that passes through a cross section of the convection column above a fire that is burning in a neutrally stable atmosphere.
heavy equipment & implements Communication, Education, and Prevention Committee CEPC In Development
heavy equipment transport Equipment Technology Committee ETC Approved Any ground vehicle capable of transporting a dozer, tractor, or other heavy piece of equipment.
heavy fuels Fire Use Subcommittee FUSC Approved Fuels of large diameter such as snags, logs, large limbwood, which ignite and are consumed more slowly than flash fuels.
heel of the fire Wildland Fire Investigation Subcommittee WFISC Approved That portion of a fire backing directly away from and in relatively close proximity to the ignition area. The slowest spreading portion of a fire edge and generally opposite the head.
height Fire Use Subcommittee FUSC Approved The vertical measurement of vegetation from the top of the crown to ground level.
Height Above Ground Level (HAGL) Approved A height measured with respect to the underlying ground surface.
Height Above Sea Level (HASL) Approved Height above mean sea level in feet.
held line IOSC Incident Operations Subcommittee Approved All control line that still contains the fire when mopup is completed. Excludes lost line, natural barriers not backfired, and unused secondary lines.
helibase Interagency Helicopter Operations Subcommittee IHOPS Approved The main location within the general incident area for parking, fueling, maintenance, and loading of helicopters. It is usually located at or near the incident base.
helibase crew Interagency Helicopter Operations Subcommittee IHOPS Approved A crew of individuals who may be assigned to support helicopter operations.
helibucket National Interagency Aviation Committee NIAC Approved Specially designed bucket carried by a helicopter like a sling load and used for aerial delivery of water or fire retardants.
helicopter tender Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A ground service vehicle capable of supplying fuel and support equipment to helicopters.
helicopter type (water source) Approved Largest helicopter type that can use the water source.
heliport National Interagency Aviation Committee NIAC Approved A permanent facility for the operation of helicopters which has been built to FAA standards and which is marked on aeronautical charts. Natural resource agencies refer to agency heliports as permanent helibases.
helipumper National Interagency Aviation Committee NIAC Approved Lightweight portable pump developed for transport by helicopter.
helispot National Interagency Aviation Committee NIAC Approved A natural or improved takeoff and landing area intended for temporary or occasional helicopter use.
helitack Interagency Helicopter Operations Subcommittee IHOPS Approved The utilization of helicopters to transport crews, equipment, and fire retardants or suppressants to the fireline during the initial stages of a fire. The term also refers to the crew that performs helicopter management and attack activities.
helitack crew Interagency Helicopter Operations Subcommittee IHOPS Approved A crew of firefighters specially trained and certified in the tactical and logistical use of helicopters for fire suppression.
helitank National Interagency Aviation Committee NIAC Approved Specially designed tank, generally of fabric or metal, fitted closely to the bottom of a helicopter and used for transporting and dropping suppressants or fire retardants.
helitanker National Interagency Aviation Committee NIAC Approved A helicopter equipped with a fixed tank, Airtanker Board certified, capable of delivering a minimum of 1,100 gallons of water, foam, or retardant.
helitorch Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved An aerial ignition device hung from or mounted on a helicopter to disperse ignited lumps of gelled gasoline. Used for backfires, burnouts, or prescribed burns.
herb Fire Use Subcommittee FUSC Approved A plant that does not develop woody, persistent tissue but is relatively soft or succulent and sprouts from the base (perennials) or develops from seed (annuals) each year. Includes grasses, forbs and ferns.
herbaceous fuel moisture FDSC Fire Danger Subcommittee Approved In NFDRS, a calculated value representing the approximate moisture content of the live herbaceous vegetation in the rating area expressed as a percentage of the oven dry weight of the sample.
herbaceous stage FDSC Fire Danger Subcommittee Approved The modeled condition of herbaceous vegetation (pre-green, green-up, transition, cured, frozen) for the 1978 version of NFDRS.
hidden fire scar Fire Use Subcommittee FUSC Approved Fire scar in a tree resulting from fire injury to the cambium without destruction of the overlying bark and therefore not readily discernible.
high expansion Equipment Technology Committee ETC Approved Foam with an expansion between 201:1 and 1000:1.
high fire risk day Fire Weather Subcommittee FWS Approved A day when an ignition trigger and/or significant weather trigger and an appropriate fuel dryness level combine to create conditions that historically have resulted in a significant fire event for a particular area.
high pressure fog Equipment Technology Committee ETC Approved Small capacity spray jet produced at very high pressures (greater than 250 psi, the normal maximum pressure for standard ground tankers) and discharged through a small hose with a gun-type nozzle.
hill (topographic) Incident and Position Standards Committee IPSC Approved A naturally occuring mass of earth material whose crest or summit is at a lower elevation than a mountain.
historical weather station FDSC Fire Danger Subcommittee Approved In WIMS, a weather station that is no longer in service for which access to archived observations is still available in NIFMID.
holding actions Fire Use Subcommittee FUSC Approved All actions taken to stop the spread of fire.
holding orbit IASS Interagency Aerial Supervision Subcommittee Approved A predetermined maneuver which keeps an aircraft within a specified airspace while awaiting further orders.
holding resources Fire Use Subcommittee FUSC Approved Resources assigned to do all required fire suppression work following fireline construction but generally not including extensive mopup.
holdover fire Wildland Fire Investigation Subcommittee WFISC Approved A fire that remains dormant for a considerable time.
home National Coordination System Committee NCSC Approved An adjective that describes a permanent place associated with a resource.
home assessment Communication, Education, and Prevention Committee CEPC Approved Evaluation of a dwelling and its immediate surrounding to determine its potential to escape damage by an approaching wildland fire. Includes the fuels and vegetation in the yard and adjacent to the structure, roof environment, decking and siding materials, prevailing winds, topography, fire history, etc., with the intent of mitigating fire hazards and risks. 
home dispatch unit IOSC Incident Operations Subcommittee Approved The NWCG Unit Identifier of the center primarily responsible for dispatching the resource.
Home Ignition Zone (HIZ) WMSC WUI Mitigation Subcommittee Archived The area where the factors that principally determine home ignition potential during extreme wildfire behavior (high fire intensities and burning embers) are present. The characteristics of a home and its immediate surroundings within 100 feet comprise the HIZ.
home location National Coordination System Committee NCSC Approved The physical location of a resource when not on assignment.
home unit (administrative) National Coordination System Committee NCSC Approved The administrative organization where a resource is regularly assigned or the agency location where an individual is hired or a contract is administered.
home unit (designated) Incident and Position Standards Committee IPSC Approved The designated agency or entity providing contracted resources that employs the individual who is actively pursuing a position performance assignment (completion of a position task book).
horizontal datum code Geospatial Subcommittee GSC Approved The identfication given to the reference system used for defining the coordinates of points.
horizontal fuels arrangement Fuels Management Committee FMC Approved Composition of fuel laterally across the landscape.
hose clamp Equipment Technology Committee ETC Approved Crimping device for stopping the flow of water in a hose.
hose lay IOSC Incident Operations Subcommittee Approved Arrangement of connected lengths of fire hose and accessories on the ground, beginning at the first pumping unit and ending at the point of water delivery.
hose line tee Equipment Technology Committee ETC Approved A fitting that may be installed between lengths of hose to provide an independently controlled outlet for a branch line.
hose rack Equipment Technology Committee ETC Approved Item for storing drying fire hose.
hose reel Equipment Technology Committee ETC Approved A rotating drum used for winding booster hose (normally) for storing and dispensing.
hose thread Equipment Technology Committee ETC Approved The specific dimensions of screw thread employed to coupled fire hose and equipment. American National Standards (NH) have been adopted for fire hose couplings threads in 3/4, 1-1/2, 2-1/2, 3-1/2, 4, 5, and 6-inch sizes.
hose washer Equipment Technology Committee ETC Approved Device for cleaning the exterior of fire hose.
host National Coordination System Committee NCSC Approved A term historically used to indicate the agency or unit with jurisdiction or protection responsibilities or who was financially responsible for the incident response. Its use is not recommended.
hot set Communication, Education, and Prevention Committee CEPC In Development Use of an open flame to ignite a wildfire and the source is removed from the ignition area.
hot work: welder/grinder/torch In Development Track maintenance that involves welding, soldering, cutting and brazing railroad tracks.
hot work: welder/grinder/torch/cutter Communication, Education, and Prevention Committee CEPC Superceded
hotshot crew IOSC Incident Operations Subcommittee Approved Intensively trained fire crew used primarily in handline construction (Type-1).
hotspot IOSC Incident Operations Subcommittee Approved A particularly active part of a fire.
hotspotting IOSC Incident Operations Subcommittee Approved Checking the spread of fire at points of more rapid spread or special threat. Is usually the initial step in prompt control, with emphasis on first priorities.
hover National Interagency Aviation Committee NIAC Approved A stationary in-flight condition for helicopters when no directional flight is achieved.
hover ceiling National Interagency Aviation Committee NIAC Approved Highest altitude above sea level at which a helicopter can hover at maximum computed gross weight. It is generally specified whether the quoted hover ceiling refers to hovering in ground effect (HIGE) or hovering out of ground effect (HOGE).
hover hook-up National Interagency Aviation Committee NIAC Approved Attaching of a cargo lead line to a hovering helicopter.
hoverfill National Interagency Aviation Committee NIAC Approved The process by which a helicopter fills a helibucket while hovering above the water source.
Hovering in Ground Effect (HIGE) National Interagency Aviation Committee NIAC Approved The situation in which a helicopter is hovering sufficiently close to the ground to achieve added lift due to the effects of "ground cushion." The HIGE ceiling, for a given gross weight, thus is greater than the HOGE (Hovering Out of Ground Effect) ceiling.
human-caused fire FDSC Fire Danger Subcommittee Approved Any fire caused directly or indirectly by person(s).
human-caused risk FDSC Fire Danger Subcommittee Approved A model for predicting the average number of reportable human caused fires from a given ignition component value.
human-caused risk scaling factor FDSC Fire Danger Subcommittee Approved Number relating human-caused fire incidence to the ignition component in a fire danger rating area. It is based on three to five years of fire occurrence and fire weather data that adjusts the prediction of the basic human-caused fire occurrence model to fit local experience. 
humidity Fire Weather Subcommittee FWS Approved General term referring to the moisture content of the atmosphere.
humus Fire Use Subcommittee FUSC Approved Layer of decomposed organic matter on the forest floor beneath the fermentation layer and directly above the soil. It is that part of the duff in which decomposition has rendered vegetation unrecognizable and mixing of soil and organic matter is underway.
hurricane/typhoon (event) National Coordination System Committee NCSC Approved An event dealing with response to a hurricane or typhoon.
hydrophobicity Fire Weather Subcommittee FWS Approved Resistance to wetting exhibited by some soils, also called water repellency. The phenomenon may occur naturally or may be fire-induced. It may be determined by water drop penetration time, equilibrium liquid-contact angles, solid-air surface tension indices, or the characterization of dynamic wetting angles during infiltration. 
hygrothermograph Fire Weather Subcommittee FWS Approved Recording instrument combining, on one paper record, the variation of dry-bulb temperature and relative humidity as a function of time.
I-Zone WMSC WUI Mitigation Subcommittee Archived An area that, in relation to wildland/urban fire, has a set of conditions that provides the opportunity for fire to burn from wildland vegetation to the home/structure ignition zone.
ICS 209 remarks wfnwcgorg:NISC Approved Additional information pertinent to the management of the incident.
ICS 209 report date time wfnwcgorg:NISC Approved Automated date and time stamp applied when the ICS 209 report is submitted.
ICS 209 report for time period from wfnwcgorg:NISC Approved The beginning date and time of the reporting period of an ICS 209.
ICS 209 report for time period to wfnwcgorg:NISC Approved The ending date and time of the reporting period of an ICS 209.
ICS 209 report status Approved The version of the ICS 209 report (Initial, Update, or Final).
identification run National Interagency Aviation Committee NIAC Approved Dry run over the target area by the leadplane to indicate an airtanker's flight path and target, while the airtanker pilot is observing.
igniter Wildland Fire Investigation Subcommittee WFISC Approved A pyrotechnic device specifically designed to initiate burning of a fuel mixture or propellant.
Ignition Area (IA) Wildland Fire Investigation Subcommittee WFISC Approved The smallest area that a wildland fire investigator can define based on the physical evidence of the fire pattern indicators, within the specific origin area, in which a competent ignition source came into contact with the first fuel ignited and combustion was sustained.
ignition component FDSC Fire Danger Subcommittee Approved A rating of the probability that a firebrand will cause an actionable fire.
ignition energy Fire Weather Subcommittee FWS Approved Quantity of heat or electrical energy that must be absorbed by a substance to ignite and burn.
ignition factor Wildland Fire Investigation Subcommittee WFISC Approved The individual factors which make up the ignition sequence; competent ignition source; the type and form of first fuel ignited; oxidant, plus the circumstances, actions, or natural events that allowed the factors to come together.
ignition method Fire Use Subcommittee FUSC Approved The means by which a fire is ignited, such as hand-held drip torch, helitorch, and backpack propane tanks.
ignition pattern Fire Use Subcommittee FUSC Approved Manner in which a prescribed fire is ignited. The distance between ignition lines or points and the sequence of igniting them is determined by weather, fuel, topography, firing technique, and other factors which influence fire behavior and fire effects.
ignition probability Fire Behavior Subcommittee FBSC Approved Chance that a firebrand will cause an ignition when it lands on receptive fuels.
ignition sequence Wildland Fire Investigation Subcommittee WFISC Approved The sequence or order of events that bring a competent ignition source, fuel first ignited and oxidant together allowing them to react with each other.
ignition source Communication, Education, and Prevention Committee CEPC Approved Any process or event capable of causing a fire.
ignition time Fire Behavior Subcommittee FBSC Approved Time between application of an ignition source and self-sustained combustion of a fuel.
ignition trigger Fire Weather Subcommittee FWS Approved A causative agent for wildland fire. For example, human or lightning.
illegal substance manufacture Communication, Education, and Prevention Committee CEPC In Development The production, preparation, propagation, compounding or processing of a controlled substance, either directly or indirectly or by extraction from substances of natural origin outside legally authorized facilities. The term "manufacture" includes the act of growing.
IMI Interactivity Levels Incident and Position Standards Committee IPSC Archived Standards to which IMI products are developed conforming to interactivity level(s) which are appropriate for the instructional design, strategy, media, content, and course specifications.
IMI Level 1 Interactivity Incident and Position Standards Committee IPSC Archived This is the lowest level of courseware development. It is normally a knowledge familiarity lesson, provided in a linear format (one idea after another).
IMI Level 2 Interactivity Incident and Position Standards Committee IPSC Archived This involves the recall of more information than a level 1 and allows the student more control over the lesson scenario through screen icons and other peripherals, such as light pens or touch screens. Typically level 2 is used for non-complex operations and maintenance lessons. Simple emulations or simulations are presented to the user. As an example, the user is requested to rotate switches, turn dials, make adjustments, or identify and replace a faulted component as part of a procedure. This also may include simple to standard developed graphics, and/or clip art, and video and audio clips. 
IMI Level 3 Interactivity Incident and Position Standards Committee IPSC Archived This involves the recall of more complex information (compared to levels 1 and 2) and allows the user an increased level of control over the lesson scenario through peripherals such as light pen, touch screen, track ball, or mouse. Video, graphics, or a combination of both is presented simulating the operation of a system, subsystem, or equipment to the user. The lesson scenario training material typically is complex and involves more frequent use of peripherals to affect a transfer of learning. Operation and maintenance procedures are normally practiced with level 3 scenarios and students may be required to alternate between multiple screens to keep pace with the lesson material. Multiple software branches (two to three levels) and rapid response are provided to support remediation. Emulations and simulations are an integral part of this presentation. This may also include complex developed graphics, and/or clip art, and video and audio clips.
impeller Equipment Technology Committee ETC Approved Rotating part of a centrifugal pump which imparts energy to the liquid to be moved. For shearing purposes, the impeller is on a rotating shaft within the body of liquid.
implementation plan Fire Use Subcommittee FUSC Approved The design and definition of all the activities, resources, limitations, and contingencies required for successful wildland fire management.
impulse Fire Weather Subcommittee FWS Approved A term used in weather primarily to describe a weak disturbance that does not necessarily have an associated storm center or surface low. The disturbance usually does not create severe weather and is frequently associated with a marine air push.
in-stand wind Fire Weather Subcommittee FWS Approved Wind speed within a stand at about eye level.
incendiary Wildland Fire Investigation Subcommittee WFISC Approved A burning compound or metal used to produce intense heat or flame, like a bomb.
incendiary device Communication, Education, and Prevention Committee CEPC In Development Contrivance designed and used to start a fire. 
incendiary device Wildland Fire Investigation Subcommittee WFISC Approved Contrivance designed and used to start a fire.
incendiary fire Wildland Fire Investigation Subcommittee WFISC Approved A fire that is intentionally ignited in an area or under circumstances where and when there should not be a fire.
incident National Incident Management System Integration Committee NIMSIC, FMB Fire Management Board Approved An occurrence, either human-caused or a natural phenomenon, that requires action or support by emergency services personnel to prevent or minimize loss of life or damage to property and/or natural resources.
Incident Action Plan (IAP) National Incident Management System Integration Committee NIMSIC Approved An oral or written plan containing the objectives established by the Incident Commander or Unified Command and addressing tactics and support activities for the planned operational period, generally 12 to 24 hours.
incident agency Incident Business Committee IBC Approved The organizational unit responsible for the incident activities.
incident assignment Incident Business Committee IBC Approved An assignment to an incident that requires a length of commitment.
incident base National Incident Management System Integration Committee NIMSIC Approved A location where personnel coordinate and administer logistics functions for an incident. There is typically only one base per incident. (An incident name or other designator is added to the term Base.) The ICP may be co-located with the Incident Base.
Incident Blanket Purchase Agreement (IBPA) Incident Business Committee IBC Approved A pre-season agreement for equipment, supplies, or services to be used on fire and all-hazards incidents, issued on a Solicitation/Contract/Order for Commercial Items, SF-1449 form. I-BPAs are awarded on a competitive basis using commercial item procedures.
Incident Command National Incident Management System Integration Committee NIMSIC Approved The ICS organizational element responsible for overall management of the incident and consisting of the Incident Commander or Unified Command and any additional Command Staff activated.
Incident Command Post (ICP) National Incident Management System Integration Committee NIMSIC Approved The field location where the primary functions of incident command are performed. The ICP may be co-located with the Incident Base or other incident facilities.
Incident Command System (ICS) National Incident Management System Integration Committee NIMSIC Approved A standardized approach to the command, control, and coordination of on-scene incident management, providing a common hierarchy within which personnel from multiple organizations can be effective. ICS is the combination of procedures, personnel, facilities, equipment, and communications operating within a common organizational structure, designed to aid in the management of on-scene resources during incidents. It is used for all kinds of incidents and is applicable to small, as well as large and complex, incidents, including planned events.
Incident Commander (IC) National Incident Management System Integration Committee NIMSIC Approved The individual responsible for on-scene incident activities, including developing incident objectives and ordering and releasing resources. The Incident Commander has overall authority and responsibility for conducting incident operations through a Delegation of Authority.
Incident Commander (IC) name National Coordination System Committee NCSC Approved The first (optional) and last name of the Incident Commander(s) currently assigned to the incident.
Incident Communications Center National Incident Management System Integration Committee NIMSIC Archived The location of the communications unit and the message center.
incident complex National Incident Management System Integration Committee NIMSIC Approved Two or more distinct incidents in the same general area that, by management action, are managed under a single incident commander or unified command in order to improve efficiency and simplify incident management processes.
incident complex (event) National Coordination System Committee NCSC Approved Two or more distinct incidents in the same general area that, by management action, are managed under a single incident commander or unified command in order to improve efficiency and simplify incident management processes.
Incident Complexity Level National Incident Management System Integration Committee NIMSIC Approved The incident level established by completing an incident complexity analysis considering the level of difficulty, severity, or overall resistance the incident or event presents to incident management or support personnel as they work to manage it; a categorization that helps leaders compare one type of incident or event to another.   
incident host UIB Unit Identifier Board Approved An organizational unit with jurisdictional authority responsibility for interagency incident management. 
Incident Management National Incident Management System Integration Committee NIMSIC Approved The broad spectrum of activities and organizations providing operations, coordination, and support applied at all levels of government, using both governmental and nongovernmental resources to plan for, respond to, and recover from an incident, regardless of cause, size, or complexity.
incident management organization National Coordination System Committee NCSC Approved The incident management organization for the incident.
Incident Management Team (IMT) National Incident Management System Integration Committee NIMSIC Approved A group of ICS-qualified personnel consisting of an Incident Commander, Command and General Staff, and personnel assigned to other key ICS positions.
Incident Management Team name Approved Name of the Incident Management Team in charge of the fire.
Incident Medical Specialist Program Risk Management Committee RMC Approved An incident-based program to care for emergent and minor medical as well as common occupational health care problems of incident personnel. This program may be deployed to Type I and Type II incidents. Currently, this program is only available in three regions: Northwest (R6), Northern Rockies (R1) and Alaska (R10). In Alaska, the program is known as the Alaska Fire Medic Program.
incident name FRSC Fire Reporting Subcommittee Approved The name assigned to an incident.
incident objectives National Incident Management System Integration Committee NIMSIC Approved A statement of an outcome to be accomplished or achieved. Incident objectives are used to select strategies and tactics. Incident objectives should be realistic, achievable, and measurable, yet flexible enough to allow strategic and tactical alternatives.
incident order number Incident Business Committee IBC Approved The number assigned to an incident. This number follows a standard format where the first two letters indicate the state, the next letters are the incident agency, and the last six digits are agency assigned.
incident organization National Incident Management System Integration Committee NIMSIC Pending Archive Resources, together with a complement of overhead personnel, calculated to be sufficient to provide fire efficient incident management.
incident overhead National Incident Management System Integration Committee NIMSIC Pending Revision All supervisory positions described in the Incident Command System.
incident personnel National Incident Management System Integration Committee NIMSIC Approved All individuals assigned to an incident or in support of an incident, whether on scene or off scene.
incident personnel fatality quantity Risk Management Committee RMC Approved The total number of deaths, connected with the performance of work duties, that occurred in conjunction with an incident.
incident personnel injury illness quantity Risk Management Committee RMC Approved Total number of reportable occupational injuries and illnesses, which resulted in lost work days, that occurred in conjunction with an incident. Also includes cases without lost work days which result in transfer to another job, termination of employment, or required medical treatment (other than first aid); or which involved loss of consciousness, or restriction of work or motion. (First aid and lost work days are further defined under OSHA Part 1904.)
incident position standards NWCG-EB NWCG Executive Board Archived Incident Position standards are a component of NWCG standards. They enable consistent and uniform performance by personnel mobilized by position under NIMS-ICS principles. Incident position standards include incident position descriptions (duties and responsibilities) and position qualification requirements for training, experience, physical fitness, and position currency.
incident qualifications card Incident and Position Standards Committee IPSC Approved A card issued to persons showing their incident management and trainee qualifications to fill specified fire management positions in an incident management organization.
incident short description NICADS National Interagency Computer Aided Dispatch Approved General descriptive location of the incident as it relates to an identifiable town or population center. In the case of a Complex, this may describe 1) one of the points of origin of one of the member or “child” incidents, or 2) a center or other representative point that related to the group of incidents.
incident size Incident and Position Standards Committee IPSC Approved How large the incident is, measured in acres. This number can change over the life of the incident.
incident supply cache UIB Unit Identifier Board Approved An organizational unit representing a facility where tools, equipment, and/or supplies are stored and made available for incident use through the national ordering system.
incident support cache Incident Business Committee IBC Approved Refers to type 1 (national interagency support cache), type 2 (national interagency support cache satellite), and type 3 (local interagency support cache). Caches may consist of a pre-determined complement of tools, equipment and/or supplies stored in a designated location, available for incident use.
incident support organization National Incident Management System Integration Committee NIMSIC Pending Revision Includes any off-incident support provided to an incident. Examples would be agency dispatch centers, airports, mobilization centers, etc.
Incident Type Category (fire) Approved A sub‐group of the Incident Type Kind "Fire" that describes the types of incident or planned event to which the interagency wildland fire community responded to.
incident type endorsement Incident and Position Standards Committee IPSC Approved The type of incident for which a resource is qualified to perform in a position.
incident weather forecast Fire Weather Subcommittee FWS Approved A special weather forecast for a specific incident prepared by a meteorologist on site at or near the incident area.
incident with potential Risk Management Committee RMC Approved Wildland fire-related mishap that results in serious or non-serious injuries involving multiple personnel, near accident (which would have resulted in a serious injury or fatality), or substantial loss of property (less than $250,000). The mishap may be so complex and fraught with operational discrepancies that it has the potential to produce an accident, serious injury, or fatality given a similar environment or set of circumstances that existed at the time of the incident. 
incident/event support (event) National Coordination System Committee NCSC Approved An event dealing with effective and timely support by the wildland fire community of an Event Host's dispatch unit, in order to relieve the dispatch unit of increased business volume due to anticipated or existing wildland fire or event activity. This category includes activities such as expansion of the existing Incident Support Organizations (ISO), such as initiating Expanded Dispatch operations, expanding Technical Support (such as establishment of contract-resource inspection stations), Multiagency Coordinating Group (MAC Group) support, and expanding Administrative support (such as support of bill-payment centers).
increaser Equipment Technology Committee ETC Approved Increasing coupling used on hose, pump, or nozzles to permit connection of a larger size of hose.
increment IOSC Incident Operations Subcommittee Archived Any resource or grouping of resources on which individual status is maintained.
incremental drop SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved Airtanker drop in which tank doors are opened in sequence so that fire retardant cascades somewhat continuously.
independent action IOSC Incident Operations Subcommittee Approved Fire suppression activities by other than regular fire suppression organizations or a fire cooperator.
independent crown fire Fire Behavior Subcommittee FBSC Approved A fire that advances in the tree crowns alone, not requiring any energy from the surface fire to sustain combustion or movement.
Indicated Airspeed (IAS) National Interagency Aviation Committee NIAC Approved The speed of an aircraft as shown on its pitot static airspeed indicator. Calibrated to reflect standard atmosphere adiabatic compressible flow at sea level, uncorrected for airspeed system errors.
indicator Wildland Fire Investigation Subcommittee WFISC Approved Visual remains at a fire scene revealing the fire's progress and action.
indicator categories Communication, Education, and Prevention Committee CEPC Approved Classification of indicators into a variety of categories based on how they are formed and the types of material they are found on.
indirect attack IOSC Incident Operations Subcommittee Approved A method of suppression in which the control line is located some considerable distance away from the fire's active edge. Generally done in the case of a fast-spreading or high-intensity fire and to utilize natural or constructed firebreaks or fuel breaks and favorable breaks in the topography. The intervening fuel is usually backfired; but occasionally the main fire is allowed to burn to the line, depending on conditions. 
inductor Equipment Technology Committee ETC Approved A control mechanism that allows a regulated quantity of foam concentrate to be introduced into the main hose line.
Industrial Fire Precaution Level (IFPL) FDSC Fire Danger Subcommittee Approved An application of fire danger rating to support regulation of contractors involved in land management activities for fire prevention purposes in the Pacific Northwest.
inert target shooting Communication, Education, and Prevention Committee CEPC In Development
Infrared (IR) Fire Weather Subcommittee FWS Approved A heat detection system used for fire detection, mapping, and hotspot identification.
Infrared (IR) Groundlink Fire Weather Subcommittee FWS Approved A capability through the use of a special mobile ground station to receive air-to-ground IR imagery at an incident.
infrastructure event (event) National Coordination System Committee NCSC Approved An event dealing with public infrastructure such as water, electricity, transportation, or communication networks.
inhibition Equipment Technology Committee ETC Approved Process of extinguishing fire by the use of an agent that interrupts the chemical reactions in the combustion process.
inhibitor Equipment Technology Committee ETC Approved Any agent which retards a chemical reaction.
initial action FMB Fire Management Board Approved See initial response.
initial action date time FRSC Fire Reporting Subcommittee Approved The date and time that initial action was taken by the first resources to arrive at a fire.
Initial Attack (IA) FMB Fire Management Board Approved An aggressive action to put the fire out by the first resources to arrive, consistent with firefighter and public safety and values to be protected.
initial attack crew IOSC Incident Operations Subcommittee Approved Specially trained and equipped fire crew for initial attack on a fire.
Initial Attack Fire (IAF) IOSC Incident Operations Subcommittee Approved Fire that is generally contained by the attack units first dispatched, without a significant augmentation of reinforcements, within two hours after initial attack, and full control is expected within the first burning period.
Initial Attack Incident Commander (IAIC) IOSC Incident Operations Subcommittee Archived The incident commander at the time the first attack forces commence suppression work on a fire.
initial fire strategy In Development The fire strategy initially used on a wildland fire; the general plan or direction utilized until it succeeds or changes. 
initial fire strategy designator FRSC Fire Reporting Subcommittee Approved The fire strategy initially used on a wildland fire. The initial fire strategy is the general plan or direction utilized until it succeeds or changes. The NWCG glossary defines strategy as: The general plan or direction selected to accomplish incident objectives.
initial fire strategy met indicator FRSC Fire Reporting Subcommittee Approved Indicates whether the objectives for the initial fire strategy were attained. NWCG glossary defines strategy as: The general plan or direction selected to accomplish incident objectives
initial investigative area Wildland Fire Investigation Subcommittee WFISC Approved The area where investigator(s) begin their on-scene search for the general origin area.
initial response FMB Fire Management Board Approved The initial decisions and actions taken in reaction to a reported incident.
initial response resource quantity FRSC Fire Reporting Subcommittee Approved The total number of fire resources by kind, category, and type (if listed and applicable) used during the initial response. Initial response resouces will only be counted during intial attack. Extended Attack Incidents are those which persist beyond the first full operational period where local resources are not sufficient and the complexity elevates beyond initial attack commander capability.
inmate crew IOSC Incident Operations Subcommittee Approved Any fire crew composed of prison inmates or wards.
Inside Diameter (ID) Equipment Technology Committee ETC Approved The internal diameter of a tube, conductor, or coupling, as distinguished from its OD (Outside Diameter). Fire hose sizes are classified by a nominal internal diameter.
Instrument Flight Rules (IFR) Conditions National Interagency Aviation Committee NIAC Approved Weather conditions below the minimum for flight under Visual Flight Rules and therefore requiring the observance of instruments inside the aircraft for controlling flight; generally considered to be less than 1000' AGL and 3 miles distant.
Instrument Landing System (ILS) National Interagency Aviation Committee NIAC Approved System for airplane landing in which the pilot is guided by radio beams.
instrument shelter FDSC Fire Danger Subcommittee Approved Naturally or artificially ventilated structure, constructed to specifications and used to shield weather measuring instruments from direct sunshine and precipitation.
Integrated Reporting of Wildland Fire Information Identifier Approved Primary key for linking to the Wildland Fire Locations Point dataset.
Interactive Multimedia Instruction (IMI) Incident and Position Standards Committee IPSC Archived A group of predominantly interactive, electronically delivered training. IMI products include instructional software and software management tools used in support of instructional programs. IMI products are teaching and management tools and may be used in combination or individually. Used individually, not all IMI products can be considered interactive, multimedia, or instructional. However, IMI products, when used in combination with one another, are interactive, multimedia, and instructional. IMI technology is one of the primary technologies to be used in distance learning. 
Interagency Authoritative Data Source (IADS) Data Management Committee DMC Approved A product, tool, or IT application that has been designated as the trusted source for wildland fire data. This source may also create and update transactional data for use in other applications. There may be more than one IADS and it can change depending on business process complexity and life cycle. An IADS may be a compilation or subset of data from other authoritative sources. The DLM process ensures sources, limitations, currency, and attributes for the IADS are documented.
Interagency Resources Representative (IARR) IOSC Incident Operations Subcommittee Archived An individual who may be assigned to or requested by an incident to serve as the sending unit's representative to oversee the care and treatment of crews, overhead, and equipment assigned to an incident.
Interagency System of Record (ISOR) Data Management Committee DMC Approved Agencies and bureaus may have their own SOR for their data. An ISORs are identified by an interagency business area as the official application source of interagency data. An ISOR is the source that resolves duplicate records that may arise from various IADSs and ensures the data meets defined quality standards before it is included in official historical data sets. An ISOR can be an external source of data used by wildland fire.
interchangeable course Incident and Position Standards Committee IPSC Archived A course developed by an interagency, all-hazard subject matter expert group containing the same learning objectives and content as an NWCG developed course. Interchangeable course do not require equivalency determination by a using agency and may have multiple course codes and/or numbers. These courses will be incorporated into IQCS/IQS and credit will be given for the NWCG course. 
intermittent IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Employing office is a government or contractor entity There is no set work schedule; the person is in a “call-when-needed” status. Employee receives compensation for work
intermittent smoke Fire Behavior Subcommittee FBSC Approved Smoke which becomes visible only at intervals.
internal load National Interagency Aviation Committee NIAC Approved Load carried inside the fuselage structure of an aircraft.
internal payload National Interagency Aviation Committee NIAC Approved Allowable aircraft cabin load, in pounds, with full fuel and pilot in calm air at standard atmosphere.
international mobilization (event) National Coordination System Committee NCSC Approved An event dealing with effective and timely support to the wildland fire community by mobilizing resources internationally. This category includes importing and exporting resources.
invasive concern Approved A list of invasive species that are cause for concern related to the use of water sources.
inventoried resources IOSC Incident Operations Subcommittee Archived Assigned resources which have checked in at the incident.
inversion Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved Atmospheric inversion. The departure from the usual increase or decrease with altitude of the value of an atmospheric property. In fire management usage, nearly always refers to an increase in temperature with increasing height. Also, the layer through which this departure occurs (also called inversion layer.) The lowest altitude at which the departure is found is called the base of the inversion.
Iron Pipe Thread (IPT) Equipment Technology Committee ETC Approved A tapered thread standard that is used for connecting various sizes of rigid pipe. This standard may be referred to as tapered iron pipe thread (TIPT), National pipe thread (NPT), iron pipe thread (IPT), or iron pipe standard thread (IPS). With tapered thread, the threads and pipe sealant perform the seal at the connection. This is opposed to straight thread connectors which use a gasket to form the seal. 
is available (water source) Approved Indicates that a water source is available for fire purposes.
is location tracking enabled National Coordination System Committee NCSC Approved Indicates whether a resource's location (geometry object/shape) is being updated by a real-time GPS tracking such as AVL (Automated Vehicle Locator).
is national resource National Coordination System Committee NCSC Approved Indicates whether a resource is a National Resource for use in Initial Response.
is primary capability Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Indicates that the capability is the primary capability for the equipment or aircraft.
is valid (resource) National Coordination System Committee NCSC Approved Indicates whether a resource is valid for use in Initial Response. Invalid resources should be removed from the data stream
is visible Approved Provides a flag for mapping display.
island Fire Use Subcommittee FUSC Approved An unburned area within a fire perimeter.
isobar Fire Weather Subcommittee FWS Approved A line connecting points of equal atmospheric pressure on a weather map.
isotherm Fire Weather Subcommittee FWS Approved A line connecting points of equal temperature on a weather map.
isothermal layer Fire Weather Subcommittee FWS Approved Layer through which temperature remains constant with elevation.
jackpot burn Fuels Management Committee FMC Approved A fire treatment type. A prescribed fire to deliberately burn natural or modified concentrations (jackpots) of wildland fuels under specified environmental conditions, which allows the fire to be confined to a predetermined area and produces the fireline intensity and rate of spread required to attain planned resource Management Objectives.
jettison National Interagency Aviation Committee NIAC Approved Disposing of cargo, fuel, water or retardant overboard to lighten an aircraft or to improve its stability.
job aid Incident and Position Standards Committee IPSC Approved Detailed information needed to complete each task including step-by-step explanations, checklists, diagrams and other relevant information. Job aids are for use by trainees as an on-the-job training tool and as a field operational tool for qualified personnel.
job hazard analysis Risk Management Committee RMC Approved A job hazard analysis identifies hazards associated with work projects and worksites, and identifies protective equipment or modified work procedures needed.
Joint Information Center (JIC) National Incident Management System Integration Committee NIMSIC Pending Revision A facility established as the central point of contact for news media and interest parties to coordinate incident information activities at the scene of the incident. Public information officials from all participating federal, state, and local agencies should collocate at the JIC. 
Joint Information System (JIS) National Incident Management System Integration Committee NIMSIC Pending Revision A system that integrates incident information and public affairs into a cohesive organization designed to provide consistent, coordinated, timely information during crisis or incident operations.
jump spot IOSC Incident Operations Subcommittee Approved Selected landing area for smokejumpers.
jump suit Equipment Technology Committee ETC Approved Approved protection suit worn for smokejumping.
jurisdiction Data Management Committee DMC Approved The range or sphere of authority. Public agencies have jurisdiction at an incident related to their legal responsibilities and authority for incident mitigation. Jurisdictional authority at an incident can be political/geographical (e.g., city, county, state or federal boundary lines), or functional (e.g., police department, health department, etc.). 
jurisdiction (radio frequency) Approved Jurisdiction of initial attack frequency zones in a dataset.
jurisdictional agency National Incident Management System Integration Committee NIMSIC Approved The agency having responsibility either geographical or functional, related to their legal responsibilities and authorities.
jurisdictional agency category In Development The agency category having land and resource management responsibility for a specific geographical or functional area as provided by federal, state or local law.
jurisdictional agency kind In Development The agency kind having land and resource management responsibility for a specific geographical or functional area as provided by federal, state or local law.
jurisdictional unit FRSC Fire Reporting Subcommittee Approved The governmental entity having overall land and resource management responsibility for a specific geographical area as provided by law.
jurisdictional unit identifier FRSC Fire Reporting Subcommittee Approved Code used in interagency wildland fire to uniquely identify the governmental entity having overall land and resource management responsibility for a specific geographical area as provided by law.
jurisdictional unit name In Development The name of the governmental entity having overall land and resource management responsibility for a specific geographical area as provided by law.
Keetch-Byram Drought Index (KBDI) FDSC Fire Danger Subcommittee Approved An estimate (0-800) of the amount of precipitation (in 100ths of inches) needed to bring the top 8 inches of soil back to saturation. A value of 0 is complete saturation of the soil, a value of 800 means 8.00 inches of precipitation would be needed for saturation. In the 1988 version of NFDRS, outputs of KBDI are used to adjust live and dead fuel loadings. 
Kind National Incident Management System Integration Committee NIMSIC Approved As applied to incident resources, a class or group of items or people of the same nature or character or classified together because they have traits in common. Category sometimes referred to as subset of kind.
kindling point Fire Behavior Subcommittee FBSC Approved Lowest temperature at which sustained combustion can be initiated for a specified substance.
knock down IOSC Incident Operations Subcommittee Approved To reduce the flame or heat on the more vigorously burning parts of a fire edge.
knot Fire Weather Subcommittee FWS, National Interagency Aviation Committee NIAC Approved Nautical miles per hour, equal to 1.15 mph.
label Approved The label applied to the feature in a GIS system.
ladder fuels Fire Behavior Subcommittee FBSC Approved Fuels which provide vertical continuity between strata, thereby allowing fire to carry from surface fuels into the crowns of trees or shrubs with relative ease. They help initiate and assure the continuation of crowning.
land occupancy fire Wildland Fire Investigation Subcommittee WFISC Approved Fire started as a result of land occupancy for agricultural purposes, industrial establishment, construction, maintenance and use of rights-of-way, and residences, except equipment use and smoking.
land use plan Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved A set of decisions that establish management direction for land within an administrative area; an assimilation of land-use-plan-level decisions developed through the planning process regardless of the scale at which the decisions were developed.
Land/Resource Management Plan (L/RMP) FMB Fire Management Board Approved A document prepared with public participation and approved by an agency administrator that provides general guidance and direction for land and resource management activities for an administrative area. The L/RMP identifies the need for fire’s role in a particular area and for a specific benefit. The objectives in the L/RMP provide the basis for the development of fire management objectives and the fire management program in the designated area.
landmark Incident and Position Standards Committee IPSC Approved A feature in the landscape which can be readily recognized; anythign from a prominent tree or rock, to a church or a lake.
landowner Data Management Committee DMC Approved The person or entity that owns the land or has the authority to convey title to others.
landowner category FRSC Fire Reporting Subcommittee Approved Specific classification of landownership within landowner kinds.
landowner category (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved Agency or entity having the land management responsibility at the point of origin.
landowner category (polygon)
landowner category (water source) Approved The person or entity who owns the land where the water source is located.
landowner contact information Approved Full contact information for the landowner including name, phone number, email, etc.
landowner kind FRSC Fire Reporting Subcommittee Approved Broadest classification of landownership.
landowner kind (Point of Origin) (POO) Approved Broad classification of land ownership at the point of origin.
landowner kind (polygon) Geospatial Subcommittee GSC Approved The landowner category value associated wtih the polygon.
landowner unit (Point of Origin) Approved NWCG Unit Identifier of landowner agency at the point of origin of a fire.
landslide/mass earth movement/avalanche/sinkhole (event) National Coordination System Committee NCSC Approved An event dealing with response to mass movement of the earth's surface, including landslide, mudslide, slumping, sinkhole etc.
lapse rate Fire Weather Subcommittee FWS Approved Change of an atmospheric variable (temperature unless specified otherwise) with height.
large aircraft National Interagency Aviation Committee NIAC Approved Aircraft in which maximum certified gross weight at take-off exceeds 12,500 pounds.
large fire (behavior) IOSC Incident Operations Subcommittee, Fire Environment Committee FENC Approved A fire burning with a size and intensity such that its behavior is determined by interaction between its own convection column and weather conditions above the surface.
large fire (statistical) IOSC Incident Operations Subcommittee, Fire Environment Committee FENC Approved For statistical purposes, a fire burning more than a specified area of land e.g., 300 acres.
large fire-day FDSC Fire Danger Subcommittee Approved In FireFamily Plus, a day with both a weather observation and at least one large (as defined by the user) fire.
last name Data Management Committee DMC Approved The last name of the resource as it appears on a government issued ID. 
last used (water source) Geospatial Subcommittee GSC Approved Date the water source was last used or visited and confirmed to be viable
lateral fire Wildland Fire Investigation Subcommittee WFISC Approved Rate or spread and intensity of a fire usually falling somewhere in between advancing and backing with spread lateral to the main direction of fire travel.
latitude (Decimal Degrees) Geospatial Subcommittee GSC Approved The angular distance north or south of the earth's equator, measured in units of decimal degrees along a meridian.
latitude (Decimal Degrees) (Point of Origin) FRSC Fire Reporting Subcommittee Approved The latitude location of the wildland fire location point specified in decimal degrees.
latitude (Degrees Decimal Minutes) Latitude in degrees, decimal minutes WGS84 for labeling purposes.
latitude (initial) National Coordination System Committee NCSC, Geospatial Subcommittee GSC Approved The location coordinate for the latitude value corresponding to the initial reported point of origin specified in decimal degrees.
latitude (Point of Origin) (POO) Approved The latitude location of the point of origin specified in decimal degrees. Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
law enforcement (internal) (event) National Coordination System Committee NCSC Approved An event dealing with the agency's law enforcement program. Includes non-fire infrared flights, surveillance, etc.
lead line National Interagency Aviation Committee NIAC Approved Line or set of lines made of rope, webbing, or cable and used in helicopter external load operations; usually placed between a swivel or the cargo hook and the load.
leader National Incident Management System Integration Committee NIMSIC Approved The ICS title for an individual who is responsible for supervision of a unit, strike team, resource team, or task force.
leaders intent Leadership Committee LC Approved A concise statement that outlines what individuals must know in order to be successful for a given assignment. The intent communicates three essential pieces of information: Task - What is the goal or objective Purpose - Why it is to be done End state - How it should look when successfully completed
leadership Leadership Committee LC Approved The art of providing purpose, direction, and motivation to a group of people in order to accomplish a mission and improve the organization. Leaders provide purpose by clearly communicating their intent and describing the desired end state of an assignment to their followers. Leaders provide direction by maintaining standards of performance for their followers. Leaders provide motivation by setting the example for their followers.
leadplane National Interagency Aviation Committee NIAC Approved Aircraft with pilot used to make trial runs over the target area to check wind, smoke conditions, topography and to lead airtankers to targets and supervise their drops.
leapfrog method IOSC Incident Operations Subcommittee Approved A system of organizing workers in fire suppression in which each crew member is assigned a specific task such as clearing or digging fireline on a specific section of control line, and when that task is completed, passes other workers in moving to a new assignment. 
Learning Content Management System (LCMS) Incident and Position Standards Committee IPSC Archived Any system that keeps learner information, can launch and communicate with SCOs, and can interpret instructions that tell it which SCO comes next.
learning objective Incident and Position Standards Committee IPSC Archived A description of the intended outcome of a training class, program, or evolution. The learning objective identifies the condition, the task, and the standard to which the student much achieve.
learning objects Incident and Position Standards Committee IPSC Archived Reusable learning objects represent an alternative approach to content development. In this approach, content is broken down into chunks. From a pedagogical perspective, each chunk might play a specific role within an instructional design methodology. Such chunks are called learning objects. There is no standard for the size (or granularity) of a learning object. Larger learning objects are typically harder to reuse, and smaller learner objects save less work for those who reuse them. Normally the happy medium has been estimated as between five and fifteen minutes of learning material. The requirements for each chunk are: Each chunk must be able to communicate with learning systems using a standardized method that does not depend on the system. What happens within a chunk is the chunk's business. How a learner moves between chunks is controlled by the learning system. Each chunk must have a description (metadata tag) that enables designers to search for and find the right chunk for the right job.
legend Incident and Position Standards Committee IPSC Approved A key accompanying a map which shows information needed to interpret that map. Each type of map has information represented in a different way relating to its subject matter. The legend can explain map scales, symbols and color.
legitimate smoke Fire Use Subcommittee FUSC Approved Smoke from any authorized use of fire (e.g., locomotive, industrial operations, permitted debris burning).
level of certainty Wildland Fire Investigation Subcommittee WFISC Approved Describes how strongly a fire investigator holds an opinion or conclusion, includes two levels, Possible and Probable.
level of service IFPC Interagency Fire Planning Committee Approved Amount of fire prevention and fire suppression supplied; may be expressed several ways (e.g., percent of people or buildings protected, area protected, dollar value of property protected, firefighters per capita, water flow capability).
license plate number Equipment Technology Committee ETC Approved The vehicle’s license plate number for purposes of identifying equipment.
life-safety Risk Management Committee RMC Approved Refers to the joint consideration of both the life and physical well-being of individuals.
lifting processes Fire Weather Subcommittee FWS Approved Any of the processes that lead to upward vertical motion in the atmosphere. These processes may include low level convergence, heating or thermal convection, orographic lifting over the mountains, and frontal lifting.
light (duty level) Risk Management Committee RMC Approved Light duty mainly involves office-type work with occasional field activity characterized by light physical exertion requiring basic good health.  Individuals almost always can govern the extent and pace of their physical activity.  Essential functions include, but are not limited to: climbing stairs, standing, operating a vehicle, and long hours of work, as well as some bending, stooping, or light lifting.
light (fine) fuels Fire Behavior Subcommittee FBSC Approved Fast-drying fuels, generally with a comparatively high surface area-to-volume ratio, which are less than 1/4-inch in diameter and have a timelag of 1 hour or less. These fuels readily ignite and are rapidly consumed by fire when dry.
light wind Fire Weather Subcommittee FWS Approved Wind speed less than 7 mph (6 knots) measured at 20 feet above ground. At eye level, light winds are less than 3 mph (3 knots).
lighter/matches Communication, Education, and Prevention Committee CEPC In Development Common tools used to ignite cigarettes, cigars, campfires and other items.
lighting (aviation obstruction) Approved Indicates if the aviation obstacle is lighted.
lightning Communication, Education, and Prevention Committee CEPC In Development
Lightning Activity Level (LAL) FDSC Fire Danger Subcommittee Approved A number, on a scale of 1 to 6, which reflects frequency and character of cloud-to-ground lightning (forecasted or observed). The scale for 1 to 5 is exponential, based on powers of 2 (i.e., LAL 3 indicates twice the lightning of LAL 2). LAL 6 is a special category for dry lightning and is closely equivalent to LAL 3 in strike frequency. 
lightning fire Fire Weather Subcommittee FWS, Wildland Fire Investigation Subcommittee WFISC Approved Wildfire caused directly or indirectly by lightning.
lightning fire occurrence index FDSC Fire Danger Subcommittee Approved Numerical rating of the potential occurrence of lightning-caused fires.
Lightning Risk (LR) FDSC Fire Danger Subcommittee Approved A number related to the expected number of cloud-to-ground lightning strokes to which a protection unit is expected to be exposed during the rating period. The LR value used in the occurrence index includes an adjustment for lightning activity experienced during the previous day to account for possible holdover fires. 
lightning risk scaling factor FDSC Fire Danger Subcommittee Approved Factor derived from local thunderstorm and lightning-caused fire records that adjusts predictions of the basic lightning fire occurrence model to local experience, accounting for factors not addressed directly by the model (e.g., susceptibility of local fuels to ignition by lightning, fuel continuity, topography, regional characteristics of thunderstorms). 
lightning stroke counter Fire Weather Subcommittee FWS Approved Electronic sensor used to record the number of lightning strokes within a predetermined range over a specified period of time.
lightweight debris Wildland Fire Investigation Subcommittee WFISC Approved Ash and other materials found on other remains at a fire scene which have a tendency to settle on top of the other objects.
limbing Hazard Tree and Felling Subcommittee HTTFS Approved Removing branches from a felled or standing tree, or from brush.
limitations (water source) Approved Limitation of the water source like duration of use, seasonality, slow refill, must have specific size screen on draft hose, etc.
limited containment IOSC Incident Operations Subcommittee Approved Halting of fire spread at the head, or that portion of the flanks of a prescribed fire that is threatening to exceed prescription criteria, and ensuring that this spread rate will not be encountered again; does not indicate mopup.
line cutter IOSC Incident Operations Subcommittee Approved Fire crew member in the progressive method of line construction who cuts and clears away brush, small saplings, vines, and other obstructions in the path of the fireline; usually equipped with ax or brush hook, or pulaski.
line date time FRSC Fire Reporting Subcommittee Approved The date and time that the fire perimeter was collected in the field.
line officer wfnwcgorg:ICSC Approved Managing officer, or designee, of the agency, division thereof, or jurisdiction having statutory responsibility for incident mitigation and management.
line scout IOSC Incident Operations Subcommittee Approved A firefighter who determines the location of a fire line.
lined fire hose Equipment Technology Committee ETC Approved Fire hose with a smooth inner coating of rubber or plastic to reduce friction loss.
lined hose MFES Mobile Fire Equipment Subcommittee Approved A hose that is lined with a tube of petroleum-based thermoplastic or polyester elastomer.
Liquid Concentrate (LC) Equipment Technology Committee ETC Approved Liquid phosphate fertilizers used as fire retardants, usually diluted three to five times prior to application.
litter Fire Use Subcommittee FUSC Approved The top layer of forest floor, composed of loose debris of dead sticks, branches, twigs, and recently fallen leaves or needles; little altered in structure by decomposition.
little change Fire Weather Subcommittee FWS Approved Insignificant change in wind speed, direction, and temperature (less than 5 degrees) and relative humidity (less than five percent), respectively. When used as a general statement in a long-range forecast, all four criteria apply.
live fuel moisture content FDSC Fire Danger Subcommittee Approved Ratio of the amount of water to the amount of dry plant material in living plants.
live fuels FDSC Fire Danger Subcommittee Approved Living plants, such as trees, grasses, and shrubs, in which the seasonal moisture content cycle is controlled largely by internal physiological mechanisms, rather than by external weather influences.
live herbaceous moisture content FDSC Fire Danger Subcommittee Approved Ratio of the amount of water to the amount of dry plant material in herbaceous plants (i.e., grasses and forbs).
live line Equipment Technology Committee ETC Approved Hose line filled with water under pressure and ready to use.
live reel Equipment Technology Committee ETC Approved Hose line or reel on a fire engine, carried preconnected to the pump, ready for use without making connections to pump or attaching nozzle.
live run IASS Interagency Aerial Supervision Subcommittee Approved Indicates that the airtanker has the target in sight and will make a retardant drop on this run over the target.
live woody moisture content FDSC Fire Danger Subcommittee Approved Ratio of the amount of water to the amount of dry plant material in shrubs.
load and hold National Interagency Aviation Committee NIAC Approved An order given to the airtanker pilot to pick up another load of retardant or water and hold at the reload base. The tanker is still committed to the fire.
load and return National Interagency Aviation Committee NIAC Approved Order given to the airtanker pilot to pick up another load of fire retardant or water and return to the fire.
load calculation form National Interagency Aviation Committee NIAC Approved An agency form used to calculate helicopter allowable payload.
loading pad National Interagency Aviation Committee NIAC Approved Concrete pad at a retardant base on which aircraft stand when being loaded.
Loadmaster SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved Individual responsible to the Deck Coordinator for the manifesting, loading and unloading of personnel, equipment and cargo.
local agency wfnwcgorg:ICSC Approved Any agency having jurisdictional responsibility for all or part of an incident.
local fire report identifier FRSC Fire Reporting Subcommittee Approved A number or code that uniquely identifies an incident report for a particular reporting unit and a particular calendar year.
local incident identifier FRSC Fire Reporting Subcommittee Approved A number or code that uniquely identifies an incident for a particular local fire management organization within a particular calendar year.
local resource Incident Business Committee IBC Approved Resources within a dispatch center's area of responsibility.
local responsibility area wfnwcgorg:ICSC Approved Lands on which neither the state nor the federal government has any legal responsibility for providing fire protection.
local winds Fire Weather Subcommittee FWS Approved Winds which are generated over a comparatively small area by local terrain and weather. They differ from those which would be appropriate to the general pressure pattern.
location timestamp National Coordination System Committee NCSC Approved The date/time for the resource’s last known position.
logging debris Fire Use Subcommittee FUSC Approved Unwanted tree parts (crowns, logs, uprooted stumps) remaining after harvest.
Logistics Section National Incident Management System Integration Committee NIMSIC Approved The ICS section responsible for providing facilities, services, and supplies in support of an incident and personnel well being. The logistics section may include units and branches.
long-range forecast Fire Weather Subcommittee FWS Approved Fire weather forecast for a period greater than five days in advance.
long-range spotting Fire Use Subcommittee FUSC Approved Large glowing firebrands are carried high into the convection column and then fall out downwind beyond the main fire starting new fires. Such spotting can easily occur 1/4 mile or more from the firebrand's source.
long-term fire danger Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved The results of those factors in fire danger affecting long-term planning; involves consideration of past records and conditions and probable future trends.
long-term fire residence Wildland Fire Investigation Subcommittee WFISC Approved Areas in the fire where fuel accumulations, heavy fuels, or higher fuel moisture content cause the fire to burn for an extended period of time.
long-term fire retardant Equipment Technology Committee ETC Approved Chemical that inhibits combustion primarily through chemical reactions between products of combustion and the applied chemicals, even after the water component has evaporated. Other chemical effects also may be achieved, such as film-forming and intumescence. 
longitude (Decimal Degrees) Geospatial Subcommittee GSC Approved The angular distance east or west of the prime meridian, measured in units of decimal degrees.
longitude (Decimal Degrees) (Point of Origin) Geospatial Subcommittee GSC Approved The longitude location of the wildland fire location point specified in decimal degrees.
longitude (Degrees Decimal Minutes) Geospatial Subcommittee GSC Approved Longitdue in degrees, decimal minutes WGS84 fore labeling purposes.
longitude (initial) National Coordination System Committee NCSC, Geospatial Subcommittee GSC Approved The location coordinate for the longitude value corresponding to the initial reported point of origin specified in decimal degrees.
longitude (Point of Origin) (POO) Approved The longitude location of the point of origin specified in decimal degrees. Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
longitude (World Geodetic System 1984) Approved Longitude format for labeling and display.
longline Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A line or set of lines, usually in 50' increments, used in external load operations that allow the helicopter to place loads in areas in which the helicopter could not safely land.
lookout (crew member) IOSC Incident Operations Subcommittee Approved A fire crew member assigned to observe the fire and warn the crew when there is danger of becoming trapped.
lookout (fire) IOSC Incident Operations Subcommittee Approved A person designated to detect and report fires from a vantage point.
lookout (location) IOSC Incident Operations Subcommittee Approved A location from which fires can be detected and reported.
lookout dispatcher IOSC Incident Operations Subcommittee Archived Person combining the functions of lookout and dispatcher.
lookout firefighter IOSC Incident Operations Subcommittee Archived Person combining the functions of lookout and firefighter.
lookout patrol IOSC Incident Operations Subcommittee Archived Person who travels along ridges or other vantage points to discover, detect, report, and suppress fires.
lookout point IOSC Incident Operations Subcommittee Archived Vantage point selected for fire detection or observation.
lookout tower IOSC Incident Operations Subcommittee Approved Structure that elevates a person above nearby obstructions to sight for fires; generally capped by some sort of house or cupola.
Lookout(s), Communication(s), Escape Route(s), and Safety Zone(s) (LCES) IOSC Incident Operations Subcommittee Approved Elements of a safety system used by fire fighters to routinely assess their current situation with respect to wildland firefighting hazards.
lopping Fire Use Subcommittee FUSC Approved After felling, cutting branches, tops, and unwanted boles into lengths such that resultant logging debris will lie close to the ground.
lopping and scattering Fire Use Subcommittee FUSC Approved Lopping logging debris and spreading it more or less evenly over the ground.
lost line IOSC Incident Operations Subcommittee Approved Any part of a fireline rendered useless by a breakover of the fire.
low Fire Weather Subcommittee FWS Approved An area of relatively low atmospheric pressure in which winds tend to move in a counterclockwise direction, spiraling in toward the low's center.
low expansion Equipment Technology Committee ETC Approved Foam with an expansion between 1:1 and 20:1.
luminary
luminary (aerial/ground) Communication, Education, and Prevention Committee CEPC Superceded
machine pile/slash Communication, Education, and Prevention Committee CEPC, Fire Use Subcommittee FUSC In Development Made by machine treatment of slash to reduce fire hazard or for other purposes.
macroclimate Fire Weather Subcommittee FWS Approved General large-scale climate of a large area or country as distinguished from smaller scale mesoclimate and microclimate.
macroscale fire pattern indicator Wildland Fire Investigation Subcommittee WFISC Approved Large single fire pattern indicator or overall patterns of indicators that are readily visible from a distance.
magnetic bearing Incident and Position Standards Committee IPSC Approved Bearing by magnetic north rather than true north.
magnetic north Incident and Position Standards Committee IPSC Approved The direction toward which a magnetic needle of a compass points.
main ridge IOSC Incident Operations Subcommittee Approved Prominent ridgeline separating river or creek drainages. Usually has numerous smaller ridges (spur) extending outward from both sides.
major disaster National Incident Management System Integration Committee NIMSIC Archived Any natural catastrophe or, regardless of cause, any fire, flood, or explosion, in any part of the United States, which in the determination of the President causes damage of sufficient severity and magnitude to warrant major disaster assistance.
major repair (aviation) National Interagency Aviation Committee NIAC Approved A repair (1) that, if improperly done, might appreciably affect weight, balance, structural strength, or other qualities affecting airworthiness or (2) that is not done according to accepted practices or cannot be done by elementary operations.
male coupling Equipment Technology Committee ETC Approved An externally threaded hose nipple which fits in the thread of a female (internally threaded) swivel coupling of the same pitch and diameter. Nozzles attach to this type of coupling.
management action points Fire Use Subcommittee FUSC Approved Geographic points on the ground or specific points in time where an escalation or alternative of management actions is warranted. These points are defined and the management actions to be taken are clearly described in an approved Prescribed Fire Plan. Timely implementation of the actions when the fire reaches the action point is generally critical to successful accomplishment of the objectives.
management by objectives National Incident Management System Integration Committee NIMSIC, wfnwcgorg:ICSC Approved A management approach, fundamental to NIMS, that involves (1) establishing objectives, e.g., specific, measurable and realistic outcomes to be achieved; (2) identifying strategies, tactics, and tasks to achieve the objectives; (3) performing the tactics and tasks and measuring and documenting results in achieving the objectives; and (4) taking corrective action to modify strategies, tactics, and/or performance to achieve the objectives.
management complexity level designator FRSC Fire Reporting Subcommittee Approved The highest management level utilized to manage a fire event.
management event (internal) (event) National Coordination System Committee NCSC Approved An event dealing with agency-specific administrative, programs, such as public relations.
management requirements FMB Fire Management Board Approved The technical and scientific specifications for management activities or potential actions mandated by the agency administrator and defined in land/resource management plans. Management requirements are derived from land/resource management plan and fire management plan standards and guidelines information. 
manager contact information National Coordination System Committee NCSC Approved Contact information for the manager of the resource.
managers National Incident Management System Integration Committee NIMSIC Approved Individuals within ICS organizational units that are assigned specific managerial responsibilities, e.g., staging area manager or camp manager.
manual weather station FDSC Fire Danger Subcommittee Approved A non-telemetered weather station that provides one observation every 24 hours for manual entry into WIMS.
manually regulated Equipment Technology Committee ETC Approved A proportioning method or device that requires a manual adjustment to maintain a desired mix ratio over a changing range of water flows and pressures.
map Incident and Position Standards Committee IPSC Approved A line drawing, to some scale, of an area of the earth's surface. It shows objects and features by conventional signs.
map method Geospatial Subcommittee GSC Approved How the geospatial feature was derived
map scale Incident and Position Standards Committee IPSC Approved Indicates the ratio or proportion of the horizontal distance on the map to the corresponding horizontal distance on the ground.
marine accident (event) National Coordination System Committee NCSC Approved An event dealing with an accident or mishap involving watercraft.
marine air Fire Weather Subcommittee FWS Approved Air which has a high moisture content and the temperature characteristics of an ocean surface due to extensive exposure to that surface. An intrusion of marine air will moderate fire conditions. Absence of marine air in coastal areas may lead to more severe fire danger. 
marine climate Fire Weather Subcommittee FWS Approved Regional climate under the predominant influence of the sea, that is, a climate characterized by marine air; the opposite of a continental climate.
marine search/rescue/recovery (event) National Coordination System Committee NCSC Approved An event dealing with a search, and/or rescue, and/or recovery in a marine setting.
maritime air Fire Weather Subcommittee FWS Approved Air which has assumed high moisture content and the temperature characteristics of a water surface due to extensive exposure to that surface.
mass arsonist Wildland Fire Investigation Subcommittee WFISC Approved An offender who sets three or more fires at the same location during a limited period of time.
mass fire Fire Use Subcommittee FUSC Approved A fire resulting from many simultaneous ignitions that generates a high level of energy output.
master fire chronology Fire Use Subcommittee FUSC Approved Chronological listing of the dates of fires documented in a designated area, the dates being corrected by crossdating. Size of the area must be specified.
material first ignited Wildland Fire Investigation Subcommittee WFISC Approved The fuel that is first set on fire by the heat of ignition.
mathematical model Fire Weather Subcommittee FWS Approved A model that is a quantitative and mathematical representation or simulation which attempts to describe the characteristics or relationship of physical events.
mattock Equipment Technology Committee ETC Approved Hand tool with a narrow hoeing surface at one end of the blade and a pick or cutting blade at the other end; used for digging and grubbing.
maximum certified gross weight National Interagency Aviation Committee NIAC Approved Absolute maximum allowable gross weight for an aircraft as established by the manufacturer and approved by the FAA.
maximum computed gross weight National Interagency Aviation Committee NIAC Approved Computed gross weight for an aircraft, obtained from the appropriate performance chart, which is the maximum gross weight appropriate to the applicable circumstance of configuration and/or environmental conditions.
maximum dry bulb temperature FDSC Fire Danger Subcommittee Approved The highest value for dry bulb temperature measured at the observation site during the preceding 24-hour period.
Maximum Manageable Area (MMA) Fire Use Subcommittee FUSC Approved The maximum geographic limits of spread within which a wildland fire is allowed to spread.
maximum relative humidity FDSC Fire Danger Subcommittee Approved The highest value for relative humidity measured at the observation site during the preceding 24-hour period.
may day Risk Management Committee RMC Approved International distress signal/call. When repeated three times it indicates imminent and grave danger and that immediate assistance is required.
Mcleod Equipment Technology Committee ETC Approved A combination hoe or cutting tool and rake, with or without removable blades.
mean fire return interval Fire Use Subcommittee FUSC Approved Arithmetic average of all fire intervals in a given area over a given time.
Mean Sea Level (MSL) Fire Weather Subcommittee FWS Approved Average height of the surface of the sea for all stages of the tide over a 19-year period.
measured woody fuel moisture FDSC Fire Danger Subcommittee Approved Moisture content of the small branch wood and foliage of live woody plants, expressed as a percentage of the oven dry weight of the sample, collected monthly and used to supplement NFDRS modeled outputs.
medical assist (event) National Coordination System Committee NCSC Approved An event dealing with a rescue, and/or recovery, and/or service for a non-accident medical emergency (e.g., heart attack, illness, etc.).
Medical Unit National Incident Management System Integration Committee NIMSIC Approved Medical Unit staff are responsible to plan for and provide health and medical services for incident personnel.
medium expansion Equipment Technology Committee ETC Approved Foam with an expansion between 21:1 and 200:1.
medium-range forecast Fire Weather Subcommittee FWS Approved A forecast for a period extending from about two days to five days or a week in advance; there are no absolute limits to the period embraced by this definition.
medivac Risk Management Committee RMC Approved Mobile medical treatment and transportation.
merge identifier Approved Identifies that a merge between multiple fires occurred.
merged wildfires IOSC Incident Operations Subcommittee Approved Two or more wildfires that burn together to form a single burned area and which, by management action, may be declared merged and managed as a single incident to improve efficiency and simplify incident management processes.
mesa (topographic) Incident and Position Standards Committee IPSC Approved A flat-topped mountain with steep sides.
message center National Incident Management System Integration Committee NIMSIC Archived The message center is part of the incident communications center and is collocated or placed adjacent to it. It receives, records, and routes information about resources reporting to the incident, resource status, and administrative and tactical traffic.
methodology DPMS Dispatch Position and Curriculum Management Subcommittee Approved A set of standardized procedures and practices that have been peer-reviewed and have received general acceptance by the profession.
Micro-Remote Environmental Monitoring System (Micro-REMS) Fire Weather Subcommittee FWS Approved Mobile weather monitoring station. Each unit consists of a shipping container, solar panel, battery, temperature/relative humidity sensor, wind mast, wind direction/speed sensor, data logger and radio. A Micro-REMS usually accompanies an incident meteorologist and ATMU to an incident. 
microscale fire pattern indicator Wildland Fire Investigation Subcommittee WFISC Approved Fire pattern indicators that are generally only visible when viewed within close proximity.
mid-flame windspeed Fire Weather Subcommittee FWS Approved The speed of the wind measured at the midpoint of the flames, considered to be most representative of the speed of the wind that is affecting fire behavior.
middle name Data Management Committee DMC Approved The middle name of the resource as it appears on a government issued ID. Applies only to overhead resources.
Military Operations Area (MOA) National Interagency Aviation Committee NIAC Approved Military Operations Area found on aeronautical charts.
military ordnance Communication, Education, and Prevention Committee CEPC In Development
military time IOSC Incident Operations Subcommittee Archived The 24-hour clock system where midnight is 2400, one minute after midnight is 0001 and progresses to 2400 daily.
millibar Fire Weather Subcommittee FWS Approved A unit of pressure equal to a force of 1,000 dynes per square centimeter. (A dyne is the force that would give a free mass of one gram an acceleration of one centimeter per second per second).
mineral ash Fire Behavior Subcommittee FBSC Approved The residue of mineral matter left after complete combustion of wood (wood ash) or other organic material; consists largely of oxides, carbonates, and phosphates of Ca, K and Mg, together with other compounds.
mineral soil Fire Use Subcommittee FUSC Approved Soil layers below the predominantly organic horizons; soil with little combustible material.
minimum cost suppression alternative Incident Business Committee IBC Approved The alternative that achieves incident objectives, consistent with priority for firefighter and public safety, and is least expensive when considering expected costs for fire suppression and emergency stabilization and/or rehabilitation.
minimum dry bulb temperature FDSC Fire Danger Subcommittee Approved The lowest value for dry bulb temperature measured at the observation site during the preceding 24-hour period.
Minimum Impact Strategy and Tactics (MIST) IFPC Interagency Fire Planning Committee Approved The application of strategy and tactics that effectively meet suppression and resource objectives with the least environmental, cultural and social impacts
minimum relative humidity FDSC Fire Danger Subcommittee Approved The lowest value for relative humidity measured at the observation site during the preceding 24-hour period.
minor (historical only) Communication, Education, and Prevention Committee CEPC In Development
miscellaneous fire Wildland Fire Investigation Subcommittee WFISC Approved Fire of known cause that cannot be properly classified into any of the eight standard causes of fires.
mission assignment National Incident Management System Integration Committee NIMSIC Approved A work order issued by the Federal Emergency Management Agency (FEMA), to a federal agency, directing completion of a specified task, and setting forth funding, other managerial controls and guidance. Mission Assignments (MA) are implemented utilizing assigned federal agency's existing authorities and resources which may be compensable or non-compensable.
misuse of fire by a minor Communication, Education, and Prevention Committee CEPC In Development Any unauthorized use of fire or incendiary devices by an individual under the ae of 18, including incidents caused by curiosity and exploration with fire.
mitigation FMB Fire Management Board Approved Modifying the environment or human behavior to reduce potential adverse impacts of from a natural hazard.
mitigation actions IFPC Interagency Fire Planning Committee Approved Actions that are implemented to reduce or eliminate (mitigate) risks to persons, property or natural resources. These actions can be undertaken before and during a wildfire. Before a fire actions can include fuel treatments, creation of fuel breaks or barriers around critical or sensitive sites or resources, and vegetation modification and structural changes to increase the chance a structure will survive a wildfire with or without active protection (sometimes referred to as defensible space or the home ignition zone). Mitigation actions can also occur during response and can include mechanical and physical tasks, specific fire applications, and limited suppression actions. Such as fireline construction, and creating "black lines" through the use of controlled burnouts to limit fire spread and behavior.
mix ratio Equipment Technology Committee ETC Approved The ratio of liquid foam concentrate to water, usually expressed as a percent.
mixing Fire Weather Subcommittee FWS Approved A random exchange of air parcels on any scale from the molecular to the largest eddy.
mixing chamber Equipment Technology Committee ETC Approved A tube, constructed with deflectors or baffles, that mixes foam solution and air to produce tiny, uniform bubbles in a short distance (1 to 2 ft).
mixing height Fire Weather Subcommittee FWS Approved Measured from the surface upward, the height to which relatively vigorous mixing occurs due to convection.
mixing layer Fire Weather Subcommittee FWS Approved That portion of the atmosphere from the surface up to the mixing height. This is the layer of air, usually below a stable layer, within which pollutants are mixed by turbulence and diffusion.
mixmaster National Interagency Aviation Committee NIAC Approved The person in charge of fire retardant mixing operations with responsibility for quantity and quality of the slurry and for the loading of aircraft.
mob en route Proposed New The resource is assigned to an incident and travel has started, but the resource has not yet arrived at the incident. This is the time between ETD and ETA.
mobile radio National Coordination System Committee NCSC Approved A two way radio unit on mobile apparatus (instead of base stations), usually semi-permanently attached to the apparatus.
mobile weather unit forecast (fire) Fire Weather Subcommittee FWS Approved A special fire weather forecast for a specific fire prepared by a meteorologist on site at or near the fire area.
mobile weather unit forecast (incident) Fire Weather Subcommittee FWS Approved A special weather forecast for a specific incident prepared by a meteorologist on site at or near the incident area.
mobilization National Incident Management System Integration Committee NIMSIC Approved The processes and procedures for activating, assembling, and transporting resources that have been requested to respond to or support an incident.
mobilization center National Incident Management System Integration Committee NIMSIC Approved An off-incident location at which emergency service personnel and equipment are temporarily located pending assignment, release, or reassignment.
mobilization guide National Coordination System Committee NCSC Approved A written description of procedures used by federal, state, and local organizations for activating, assembling, and transporting resources that have been requested to respond to or support an incident.
model Fire Weather Subcommittee FWS Approved A simplified or generalized representation of reality; a description, analogy, picture, or hypothesis to help visualize something that cannot be directly observed.
Model Arson Law Communication, Education, and Prevention Committee CEPC Approved Model legislation, recommended by the Fire Marshals' Association of North America and adopted in most states, dealing with the subject of arson.
Model Fireworks Law Wildland Fire Investigation Subcommittee WFISC Approved Model legislation recommended by the Fire Marshals' Association of North America and adopted by many states, regulating display of fireworks.
moderate (duty level) Risk Management Committee RMC Approved Moderate duty field work requires the average endurance and conditioning of an individual who possesses complete control of all their physical faculties. Occasional demands may be required for moderately strenuous activities in emergencies over long periods. The pace of work is usually set by the current environmental conditions.  Essential functions include, but are not limited to: considerable walking over irregular ground, standing for long periods, lifting 25 to 50 pounds, climbing, bending, stooping, squatting, twisting, and reaching.
modified by system Data Management Committee DMC Approved Username of system that modified the record.
modified on date time Data Management Committee DMC Approved Date/time that the record was modified.
Modular Airborne Firefighting System (MAFFS) Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A manufactured unit consisting of five interconnecting tanks, a control pallet, and a nozzle pallet, with a capacity of 3,000 gallons, designed to be rapidly mounted inside an unmodified C-130 (Hercules) cargo aircraft for use in cascading retardant chemicals on wildfires. 
moist adiabatic lapse rate Fire Weather Subcommittee FWS Approved Rate of decrease of temperature with increasing height of an air parcel lifted at saturation via adiabatic process through an atmosphere in hydrostatic equilibrium. Rate varies according to the amount of water vapor in the parcel and is usually between 2.0 and 5.0 degrees F per 1000 feet (3.6 and 9.2 degrees C per 1000 meters). 
moisture of extinction Fire Behavior Subcommittee FBSC Approved The fuel moisture content, weighed over all the fuel classes, at which the fire will not spread.
monitor Equipment Technology Committee ETC Approved A turret-type nozzle usually mounted on an engine.
monitoring Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved The orderly collection, analysis, and interpretation of environmental data to evaluate management's progress toward meeting objectives, and to identify changes in natural systems. Monitoring is also conducted on wildland fires to observe fire effects, fire behavior, or both. For example, the work done by Fire Effects Monitor (FEMO) or Field Observer (FOBS) positions. 
monsoon climate Fire Weather Subcommittee FWS Approved Climate characterized by (a) a long winter-spring dry season which includes a "cold season" followed by a short "hot season" immediately preceding the rains, (b) a summer and early autumn rainy season which is usually very wet (but highly variable from year to year), and (c) a secondary maximum of temperature immediately after the rainy season.
mop up IOSC Incident Operations Subcommittee Approved Extinguishing or removing burning material near control lines, felling snags, and trenching logs to prevent rolling after an area has burned, to make a fire safe, or to reduce residual smoke.
mop up crew IOSC Incident Operations Subcommittee Approved A portion or all of a regular fire crew assigned to mop up work after the fire or a portion of the fire has been contained or controlled.
mop up time IOSC Incident Operations Subcommittee Approved Elapsed time from containment or control of a fire until mopup is complete.
mosaic Fire Use Subcommittee FUSC Approved The intermingling of plant communities and their successional stages in such a manner as to give the impression of an interwoven design.
motor vehicle accident (event) National Coordination System Committee NCSC Approved An event dealing with an accident or mishap involving on- or off-highway vehicles.
move up IOSC Incident Operations Subcommittee Approved System of redistributing remaining personnel and equipment following dispatch of other forces among a network of fire stations to provide the best possible response within the fire department's direct protection area in the event of additional calls for emergency assistance. 
move up method IOSC Incident Operations Subcommittee Approved Progressive method of fireline construction on a wildfire without changing relative positions in the line. Work is begun with a suitable space between workers; whenever one worker overtakes another, all of those ahead move one space forward and resume work on the uncompleted part of the line. The last worker does not move ahead until work is completed in his/her space. Forward progress of the crew is coordinated by a crew boss. 
Multi-Agency Coordinating (MAC) Group National Incident Management System Integration Committee NIMSIC Approved A group, typically consisting of agency administrators or executives from organizations, or their designees, that provides policy guidance to incident personnel, supports resource prioritization and allocation, and enables decision making among elected and appointed officials and senior executives in other organizations, as well as those directly responsible for incident management.
Multi-Agency Coordination (MAC) National Incident Management System Integration Committee NIMSIC Approved A generalized term which describes the functions and activities of representatives of involved agencies and/or jurisdictions who come together to make decisions regarding the prioritizing of incidents, and the sharing and use of critical resources.
multi-agency incident National Incident Management System Integration Committee NIMSIC Approved An incident where one or more agencies assist a jurisdictional agency or agencies. May be single or unified command.
multicom National Interagency Aviation Committee NIAC Approved A VHF/AM aircraft radio frequency (122.9 MHz) assigned by the FAA for use in air-to-air communications.
multijurisdiction incident National Incident Management System Integration Committee NIMSIC Approved An incident requiring action from multiple agencies that have a statutory responsibility for incident mitigation. In ICS these incidents will be managed under unified command.
multiple fire situation IOSC Incident Operations Subcommittee Approved High fire frequency over a short period of time in an administrative unit, usually overtaxing the normal initial attack capability of the unit.
multiple fire-day FDSC Fire Danger Subcommittee Approved In FireFamily Plus, a day with both a weather observation and a number of fires equal to or greater than that determined by the user to be a significant workload.
multiple points of origin Wildland Fire Investigation Subcommittee WFISC Approved Two or more separate points of fire origins at a fire scene; strong indication of arson.
mutual aid Incident Business Committee IBC Approved Assistance in firefighting or investigation by fire agencies, without regard for jurisdictional boundaries.
mutual aid agreement National Incident Management System Integration Committee NIMSIC Approved A written or oral agreement between and among agencies/organizations and/or jurisdictions that provides a mechanism to quickly obtain assistance in the form of personnel, equipment, materials, and other associated services. The primary objective is to facilitate the rapid, short-term deployment of support prior to, during, and/or after an incident.
mutual threat zone IOSC Incident Operations Subcommittee Approved A geographical area between two or more jurisdictions into which those agencies would respond on initial attack.
name (water source) Approved Name of the water source.
Napalm Wildland Fire Investigation Subcommittee WFISC Approved An incendiary mixture with a jelling agent used in flamethrowers and bombs.
National Ambient Air Quality Standards (NAAQS) Fire Use Subcommittee FUSC Approved A legal limit on the level of atmospheric contamination. The level is established as the concentration limits needed to protect all of the public against adverse effects on public health and welfare, with an adequate safety margin. Primary standards are those related to health effects. Secondary standards are designed to protect the public welfare from effects such as visibility reduction, soiling, material damage and nuisances. 
National Fire Codes (NFC) IOSC Incident Operations Subcommittee Archived The collected technical fire protection standards prepared by various committees of the National Fire Protection Association and published annually in 15 volumes.
National Fire Danger Adjective Class Rating FDSC Fire Danger Subcommittee Approved The Fire Danger Adjective Class Rating representative of an area that best describes the potential initiation, spread, and difficulty of control during intial response. Fire Danger Adjective Class Rating: A method of normalizing rating classes across different fuel models, indexes, and weather station locations. It is a resultant descriptor of the combination of both constant and variable factors that affect the initiation, spread, and difficulty of control of wildfires on an area.
National Fire Danger Adjective Class Rating Code FDSC Fire Danger Subcommittee Approved The Fire Danger Adjective Class Rating representative of an area that best describes the potential initiation, spread, and difficulty of control during intial response. Fire Danger Adjective Class Rating: A method of normalizing rating classes across different fuel models, indexes, and weather station locations. It is a resultant descriptor of the combination of both constant and variable factors that affect the initiation, spread, and difficulty of control of wildfires on an area.
National Fire Danger Rating System (NFDRS) FDSC Fire Danger Subcommittee Approved A uniform fire danger rating system that focuses on the environmental factors that control the moisture content of fuels.
National Fire Danger Rating System (NFDRS) Fuel Model code FRSC Fire Reporting Subcommittee Approved A code that corresponds to one of the National Fire Danger Rating System (NFDRS) fuel models representing the predominant fuel bed properties contributing towards fire spread across the fire area.
National Fire Incident Reporting System unit identifier Approved National Fire Incident Reporting System (NFIRS) fire department ID used to uniquely identify a non-federal organizational unit (office administratively responsible for either managing incidents, providing resources, or providing logistical services).
National Fire Protection Association Standards (NFPA) NWCG-EB NWCG Executive Board Approved Standards of the National Fire Protection Association are frequently adopted by insurance agencies such as the National Board of Fire Underwriters as a basis for their regulations and used as a guide for municipal, state, or provincial laws, ordinances, and regulations. 
National Incident Management System National Incident Management System Integration Committee NIMSIC Approved A systematic, proactive approach to guide all levels of government, NGOs, and the private sector to work together to prevent, protect against, mitigate, respond to, and recover from the effects of incidents. NIMS provides stakeholders across the whole community with the shared vocabulary, systems, and processes to successfully deliver the capabilities described in the National Preparedness System. NIMS provides a consistent foundation for dealing with all incidents, ranging from daily occurrences to incidents requiring a coordinated Federal response.
National Interagency Incident Management System (NIIMS) National Incident Management System Integration Committee NIMSIC Approved An NWCG developed program that consisted of five subsystems which collectively provide a total systems approach to all-risk incident management. The subsystems are: The Incident Command System, Training, Qualifications and Certification, Supporting Technologies, and Publications Management.
National Pipe Straight Hose Thread (NPSH) Equipment Technology Committee ETC Approved This is a straight (nontapered) thread standard with the same threads per inch as the appropriate size iron pipe thread. It requires a gasket to seal and is the thread standard used by most U.S. industry.
national resource National Coordination System Committee NCSC Approved Those resources which have national utilization, high demand, limited availability, and unique status reporting requirements identified by NICC.
National Resource Lands (NRL) Incident Business Committee IBC Approved Public lands administered by the Bureau of Land Management, U.S. Department of the Interior.
National Response Framework National Incident Management System Integration Committee NIMSIC Approved An all-discipline, all-hazards plan that establishes a single, comprehensive framework for the management of domestic incidents. It provides the structure and mechanisms for the coordination of Federal support to State, local, and Tribal incident managers and for exercising direct Federal authorities and responsibilities.
National Response Plan National Incident Management System Integration Committee NIMSIC Archived A plan that integrates federal government domestic prevention, preparedness, response, and recovery plans into one all-discipline, all-hazard plan.
National Standard Thread (NH) Equipment Technology Committee ETC Approved Abbreviated (NH) for national hose. Specifically defined screw thread used on fire hose couplings.
native species Fire Use Subcommittee FUSC Approved A species which is a part of the original fauna or flora of the area in question.
natural barrier Fire Behavior Subcommittee FBSC Approved Any area where lack of flammable material obstructs the spread of wildfires.
natural disasters and severe weather (event) National Coordination System Committee NCSC Approved An event, usually managed by organizations external to the fire community, for which the primary focus is managing emergency situations created by severe weather or natural disaster.
natural fuels Fire Use Subcommittee FUSC Approved Fuels resulting from natural processes and not directly generated or altered by land management practices.
near miss Risk Management Committee RMC Approved Any potential accident which, through prevention, education, hazard reduction, or luck, did not occur.
NESDIS ID FDSC Fire Danger Subcommittee Approved An 8-character identifier assigned by NESDIS that becomes the RAWS identification number for use with the GOES satellite.
Net Value Change (NVC) Incident Business Committee IBC Approved The sum of the changes in the value of natural resources affected by a fire. The basis for computing NVC is each resource's fire-induced value change (pluses and minuses) as computed and expressed on a per unit basis.
neutral atmosphere Fire Weather Subcommittee FWS Approved Condition in which temperature decrease with increasing altitude is equal to the dry adiabatic lapse rate (i.e., the atmosphere neither aids nor hinders large-scale vertical motion).
night (aviation) National Interagency Aviation Committee NIAC Approved The time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the American Air Almanac, converted to local time.
Nitrogen Dioxide (NO2) Risk Management Committee RMC Approved The result of nitric oxide combining with oxygen in the atmosphere. A major component of photochemical smog.
Nitrogen Oxide (NO) Fire Use Subcommittee FUSC Approved Product of combustion from transportation and stationary sources and a major contributor to acid deposition and the formation of ground level ozone in the troposphere.
Nomex® Equipment Technology Committee ETC, Risk Management Committee RMC Approved Trade name for a fire resistant synthetic material used in the manufacturing of flight suits and pants and shirts used by firefighters. Aramid is the generic name.
non-attainment area Fire Use Subcommittee FUSC Approved An area identified by an air quality regulatory agency through ambient air monitoring (and designated by the Environmental Protection Agency), that presently exceeds federal ambient air standards.
non-land-based Approved An organizational unit that may be used for other incident types such as severity or support records.
non-military tracer Communication, Education, and Prevention Committee CEPC In Development
non-statistical fire FRSC Fire Reporting Subcommittee Approved Any fire not posing a threat to resources or property of the jurisdictional agency, regardless of whether action was taken by the agency.
non-statistical/other (event) National Coordination System Committee NCSC Approved An event dealing with any fire which could pose a threat to ignite adjacent wildland fuels but ultimately did not result in a wildfire and thus cannot be accurately classified as any of the other Fire (FI) categories.
nonflammable Wildland Fire Investigation Subcommittee WFISC Approved Material unlikely to burn when exposed to flame under most conditions.
nonprecision approach procedure National Interagency Aviation Committee NIAC Approved Standard aircraft instrument approach procedure in which no electronic glide slope is provided.
normal fire season (average) Fire Weather Subcommittee FWS Approved A season when weather, fire danger, and number and distribution of fires are about average.
normal fire season (period of time) Fire Weather Subcommittee FWS Approved Period of the year that normally comprises the fire season based on historical fire occurrence.
Normalized Difference Vegetation Index (NDVI) FDSC Fire Danger Subcommittee Approved A satellite observation-derived value that is sensitive to vegetative growth, measured at 1.1 km (0.6 mile) spatial and 1 week temporal scales.
not applicable (age category)
not applicable (specific cause)
not investigated Communication, Education, and Prevention Committee CEPC In Development
Notice to Airmen (NOTAM) National Interagency Aviation Committee NIAC Approved Notice identified as either a NOTAM or Airmen Advisory containing information concerning the establishment, condition, or change in any component of, or hazard in, the National Airspace System, the timely knowledge of which is essential to personnel concerned with flight operations. 
nozzle aspirated foam system Equipment Technology Committee ETC Approved A foam generating device that mixes air at atmospheric pressure with foam solution in a nozzle chamber.
nozzle operator IOSC Incident Operations Subcommittee Approved A person assigned to operate a fire hose nozzle, usually on a handline.
number [water source] Approved Number of the water source.
NWCG Standard IOSC Incident Operations Subcommittee Approved A defined behavior, action, process, or equipment type, agreed upon by the National Wildfire Coordinating Group for wildland fire performance, and is necessary to meet consistent, interagency fire management activities.
NWCG standards NWCG-EB NWCG Executive Board Approved NWCG standards establish common practices that enable efficient and coordinated national interagency wildland fire operations. These standards may be comprised of requirements, guidelines, procedures, processes, best practices, specifications, techniques, and methods. NWCG standards are interagency by design; however, the decision to adopt and utilize them is made independently by the individual member agencies and communicated through their respective directives systems.
objective (desired condition) Fire Use Subcommittee FUSC Approved A description of a desired condition; quantified and measured, and where possible, with established time frames for achievement.
objective (land management) Fire Use Subcommittee FUSC Approved Specific, achievable, measurable, time-limited results to be achieved through land management practices, either through a description of a desired condition or the degree of desired change in an attribute.
observation time Fire Weather Subcommittee FWS Approved Time of day required to record meteorological data at a fire danger station.
obstruction name Approved Common name of feature.
obstruction to vision Fire Weather Subcommittee FWS Approved Condition in which obscuring phenomenon restricts horizontal visibility to six statute miles (10 km.) or less.
obstruction type Approved Specific descriptor of aviation obstruction identified on a map.
occluded front or occlusion Fire Weather Subcommittee FWS Approved The front that is formed when and where a cold front overtakes a warm front or a stationary front.
Occurrence Index (OI) FDSC Fire Danger Subcommittee Approved A number in the National Fire Danger Rating System related to potential fire incidence within a protection unit.
Off-Road Vehicle (ORV) Equipment Technology Committee ETC Approved Any motorized vehicle designed for, or capable of, cross-country travel on or immediately over land, water, sand, snow, ice, marsh, swampland, or other terrain.
off-shift Incident Business Committee IBC Approved Non-compensable time, e.g., eating, sleeping or other activities of a personal nature.
off-site/remote assignment Incident Business Committee IBC Approved Work performed by an individual employee in support of an incident while remaining at the employee’s duty station or other designated off-site location.
Officer National Incident Management System Integration Committee NIMSIC Approved The ICS title for a member of the Command Staff authorized to make decisions and take action related to his/her area of responsibility.
official passenger National Interagency Aviation Committee NIAC Approved The following categories of personnel are official passengers: Officers and employees of the federal government traveling on official business. Members of Congress and employees of congressional committee staffs whose work relates to the agency’s programs. Non-federal passengers when engaged in missions which enhance accomplishment of an agency program such as personnel of cooperating state, county, or local agencies; representatives of foreign governments; and contractors’ representatives to include those employed by such agencies; and private citizens.
offshore flow Fire Weather Subcommittee FWS Approved Wind blowing from land to water.
OHV/ATV/motorcycle Communication, Education, and Prevention Committee CEPC In Development
oil/gas production/transportation Communication, Education, and Prevention Committee CEPC In Development The process of exploration, extraction, refining, and transportation of petroleum products. 
on-call Incident Business Committee IBC Approved Status of a federal casual or federal regular government employee used for timekeeping purposes. An employee will be considered off duty and time spent in an on-call status shall not be considered hours of work if: 1) The employee is allowed to leave a telephone number or to carry an electronic device for the purpose of being contacted, even though the employee is required to remain within a reasonable call-back radius; or 2) The employee is allowed to make arrangements such that any work which may arise during the on-call period will be performed by another person. (Reference 5 CFR 551.431(b) (1-2)). Specific state pay guidelines for non-pay status shall apply for state employees.
on-shift Incident Business Committee IBC Approved Time of actual work, ordered standby, or compensable travel with a specific start and ending time.
on-the-job training (event) National Coordination System Committee NCSC Approved An event dealing with a person's experience and proficiency while performing assigned duties while performing a job.
one lick method IOSC Incident Operations Subcommittee Approved A progressive system of building a fireline on a wildfire without changing relative positions in the line. Each worker does one to several "licks", or strokes, with a given tool and then moves forward a specified distance to make room for the worker behind.
One-hour Timelag Fuel Moisture (1-h TL FM) FDSC Fire Danger Subcommittee Approved Moisture content of one-hour timelag fuels.
one-hour timelag fuels FDSC Fire Danger Subcommittee Approved Fuels consisting of dead herbaceous plants and roundwood less than about one-fourth inch (6.4 mm) in diameter. Also included is the uppermost layer of needles or leaves on the forest floor.
One-hundred Hour Timelag Fuel Moisture (100-h TL FM) FDSC Fire Danger Subcommittee Approved The moisture content of the 100-hour timelag fuels.
one-hundred hour timelag fuels FDSC Fire Danger Subcommittee Approved Dead fuels consisting of roundwood in the size range of 1 to 3 inches (2.5 to 7.6 cm) in diameter and very roughly the layer of litter extending from approximately three-fourths of an inch (1.9 cm) to 4 inches (10 cm) below the surface.
One-thousand Hour Timelag Fuel Moisture (1,000-h TL FM) FDSC Fire Danger Subcommittee Approved The moisture content of the 1,000-hour timelag fuels.
one-thousand hour timelag fuels FDSC Fire Danger Subcommittee Approved Dead fuels consisting of roundwood 3-8 inches in diameter and the layer of the forest floor more than about 4 inches below the surface.
onshore flow Fire Weather Subcommittee FWS Approved Wind blowing from water to land.
open burning Fire Use Subcommittee FUSC Approved Burning of any fuel outdoors without the use of mechanical combustion enhancements.
open line IOSC Incident Operations Subcommittee Approved Refers to open fire front where no line has been constructed.
open trash burning Communication, Education, and Prevention Committee CEPC, Fire Use Subcommittee FUSC In Development Burning of any fuel outdoors without the use of mechanical combustion enhancements.
operating weight Interagency Helicopter Operations Subcommittee IHOPS Approved For helicopters, the equipped weight plus weight of the crew and fuel.
operational control National Interagency Aviation Committee NIAC Approved The exercise of authority over initiating, conducting, or terminating any operation. Often associated with aviation operations.
operational name National Coordination System Committee NCSC Approved The current common operational reference to a Resource, which is the name of the resource and/or call sign.
operational period National Incident Management System Integration Committee NIMSIC Approved The time scheduled for executing a given set of operation actions, as specified in the IAP. Operational periods can be of various lengths, but are typically 12 to 24 hours.
operational status National Coordination System Committee NCSC, IOSC Incident Operations Subcommittee Approved The state of a resource as it is utilized by an incident. 
operational tempo Leadership Committee LC Approved The speed and intensity of actions relative to the speed and intensity of the unfolding events in the operational environment.
Operations Area National Interagency Aviation Committee NIAC Pending New An area over an incident, whether within an FTA or TFR, where aviation operations are taking place.
Operations Coordination Center (OCC) National Coordination System Committee NCSC Approved Primary facility of the Multi-agency Coordination System (MACS); houses staff and equipment necessary to perform the MACS function.
Operations Section National Incident Management System Integration Committee NIMSIC Approved The ICS Section responsible for implementing tactical incident operations described in the IAP. In ICS, the Operations Section may include subordinate branches, divisions, and/or groups.
orbit IASS Interagency Aerial Supervision Subcommittee Approved A circular holding pattern of an aircraft around a fixed location often related to a wildland fire. For example, the circular pattern of an airtanker in the vicinity of a wildland fire, waiting to make a retardant drop.
ordered standby Incident Business Committee IBC Approved An employee is on duty, and time spent on standby duty is hours of work if, for work-related reasons, the employee is restricted by official order to a designated post of duty and is assigned to be in a state of readiness to perform work with limitations on the employee’s activities so substantial the employee cannot use the time effectively for his or her own purposes. A finding that an employee’s activities are substantially limited may not be based on the fact that an employee is subject to restrictions necessary to ensure that the employee will be able to perform his or her duties and responsibilities, such as restrictions on alcohol consumption or use of certain medications (5 CFR 551.431(a) (1)).
organic matter Fire Use Subcommittee FUSC Approved That fraction of the soil that includes plant and animal residues at various stages of decomposition, cells and tissues of soil organisms, and substances synthesized by the soil population.
organic soil Fire Use Subcommittee FUSC Approved Any soil or soil horizon containing at least 30% organic matter (e.g., muck, peat).
organization assessment IFPC Interagency Fire Planning Committee Approved The recommended organization for the incident based on analysis.
organization unit National Incident Management System Integration Committee NIMSIC Approved The organizational element having responsibility within a functional area in the incident command structure such as operations, planning, logistics or finance.
organizational unit code UIB Unit Identifier Board Approved Three to four alpha-numeric characters specific to a unit existing within the agency’s official organizational structure. The organizational unit code identifies the unit within the interagency incident management community in a common manner.
organizational unit name UIB Unit Identifier Board Approved The full name of the organization found on official documents or web sites.
organizational unit type UIB Unit Identifier Board Approved The type of organizational unit within the interagency incident management community represented by the Unit ID.
origin and/or cause not identified Communication, Education, and Prevention Committee CEPC In Development
origin destroyed Communication, Education, and Prevention Committee CEPC In Development
orographic Fire Weather Subcommittee FWS Approved Pertaining to, or caused by mountains.
orthophoto Geospatial Subcommittee GSC Approved Photograph obtained from the orthogonal (i.e., horizontal) projection of a correctly oriented stereoscopic model formed by two overlapping aerial photographs; an orthophoto is free of tilt and relief displacements.
orthophoto maps Geospatial Subcommittee GSC Approved Aerial photographs corrected to scale such that geographic measurements may be taken directly from prints. They may contain graphically emphasized geographic features and may be provided with overlays of such features as: water systems, facility location, etc. 
Osborne Firefinder IOSC Incident Operations Subcommittee Approved A sighting device used by lookouts to determine the horizontal bearing and sometimes the vertical angle of a fire from a lookout.
other (specific cause) Communication, Education, and Prevention Committee CEPC In Development A category or classification to group data points that doent fit neatly into predefined or standard categories, often used for values or entries that are uncommon or don't conform to the expected set of categories.
other causes Communication, Education, and Prevention Committee CEPC In Development Refers to wildfire ignitions not classified under common cause categories. 
other explosives Communication, Education, and Prevention Committee CEPC In Development
other land clearing Communication, Education, and Prevention Committee CEPC In Development Land clearning not covered in a traditional prescribed burn or field/ag burn.
other shooting (only for historical mapping)
other small engine equipment Communication, Education, and Prevention Committee CEPC In Development
other structure FRSC Fire Reporting Subcommittee Approved A constructed building not designed for continuous human occupancy, such as barns, commercial buildings, etc.
other structures destroyed quantity FRSC Fire Reporting Subcommittee Approved The total number of structures, other than residences, destroyed as a result of a fire.
other structures threatened quantity FRSC Fire Reporting Subcommittee Approved The total number of structures, other than residences, threatened by the fire.
other training which supports development of knowledge and skills Incident and Position Standards Committee IPSC Approved Courses defined as containing supplemental knowledge and skills not required for safe and tactical operations success on a wildfire.
out (fire) FRSC Fire Reporting Subcommittee Proposed New All observable combustion has ceased and there is no risk of the fire again becoming active and requiring additional control or management actions.
out of area response (event) National Coordination System Committee NCSC Approved An event where resources are mobilized to a Wildfire (WF) Event within their corresponding dispatch center's response area (boundary). When resources arrive on scene, it is determined the ignition is not within their area of response, but in fact plots within an adjacent dispatch center's response area (boundary).
out-of-service resources Incident Business Committee IBC Approved Resources assigned to an incident but unable to respond for mechanical, rest, or personal reasons.
outdoor oven/fireplace/metal fire ring Communication, Education, and Prevention Committee CEPC In Development
outside aid Incident Business Committee IBC Approved Firefighting assistance given to adjacent areas and nearby communities by contract or other agreement that covers conditions and payment for assistance rendered and services performed. Contrasted to mutual aid, in which neighboring firefighting organizations assist each other without charge. 
Outside Diameter (OD) Equipment Technology Committee ETC Approved External diameter of a cylinder or tube, conductor, or coupling as distinguished from the internal diameter.
overhaul Wildland Fire Investigation Subcommittee WFISC Approved Fire department procedure of inspecting premises after extinguishment of fire, to insure that fire is completely out and unable to rekindle before returning control to owner or occupants.
overhead National Incident Management System Integration Committee NIMSIC Archived Personnel assigned to supervisory positions, including incident commander, command staff, general staff, branch directors, supervisors, unit leaders, managers and staff.
overload (operational) IOSC Incident Operations Subcommittee Approved A situation that taxes an operational system to the limit of its functional capabilities. Such as too many fires for an individual unit to handle (fire overload), or too many orders for an individual dispatch center to process (dispatch overload).
overload (vehicle) Equipment Technology Committee ETC Approved Gross vehicle weight (GVW) in excess of the gross vehicle weight rating (GVWR) specified by the chassis manufacturer. Also an excess of weight over the gross vehicle axle weight rating (GAWR) specified by the chassis manufacture.
overwintering fire Fire Use Subcommittee FUSC Approved A fire that persists through the winter months until the beginning of fire season.
owner organization National Coordination System Committee NCSC Approved The agency or company to be reimbursed for providing a resource to an incident.
owner vendor Incident Business Committee IBC Approved A party that provides a contract resource for an incident.
oxidation Wildland Fire Investigation Subcommittee WFISC Approved Process during which oxygen combines with another substance.
oxidizer Wildland Fire Investigation Subcommittee WFISC Approved The portion of a chemical mixture or compound which furnishes oxygen for burning a fuel or propellant, creating an oxide.
pace Incident and Position Standards Committee IPSC Approved A pace is defined as the average length of two natural steps (a count is made each time the same foot touches the ground).
pack test Risk Management Committee RMC Approved Used to determine the aerobic capacity of fire suppression support personnel and assign physical fitness scores. The test consists of walking a specified distance, with or without a weighted pack, in a predetermined period of time, with altitude corrections. 
packing ratio Fire Weather Subcommittee FWS, Fire Environment Committee FENC Approved The fraction of a fuel bed occupied by fuels, or the fuel volume divided by bed volume.
panoramic photograph Geospatial Subcommittee GSC Approved Photographs from a lookout point, bearing azimuth and vertical angle scales, to assist in locating fires with a firefinder.
paracargo National Interagency Aviation Committee NIAC Approved Anything intentionally dropped, or intended for dropping, from any aircraft by parachute, by other retarding devices, or by free fall.
parallel attack IOSC Incident Operations Subcommittee Approved Method of fire suppression in which fireline is constructed approximately parallel to, and just far enough from the fire edge to enable workers and equipment to work effectively, though the fireline may be shortened by cutting across unburned fingers. The intervening strip of unburned fuel is normally burned out as the control line proceeds but may be allowed to burn out unassisted where this occurs without undue delay or threat to the fireline. 
parallel lane technique Wildland Fire Investigation Subcommittee WFISC Approved A search technique dividing the specific origin area into lanes that are parallel to the advancing fire progression for the purpose of a systematic examination.
parallel pumping Equipment Technology Committee ETC Approved Procedure by which the flow from two fire pumps is combined into one hose line.
parallel tandem pumping Equipment Technology Committee ETC Approved Procedure by which the flow from two fire pumps is combined into a third pump.
parameter IOSC Incident Operations Subcommittee Archived A variable which can be measured quantitatively; sometimes, an arbitrary constant; associated with populations. One of the unknown values that determine a model.
partial risk FDSC Fire Danger Subcommittee Approved Contribution of a specific source to human-caused risk, derived from the daily activity level assigned a risk source and its risk source ratio.
partial risk factor FDSC Fire Danger Subcommittee Approved Contribution to human-caused risk made by a specific risk source; a function of the daily activity level assigned that risk source and the appropriate risk source ratio.
partial-thickness burn Risk Management Committee RMC Approved A burn where the outer layer of skin is burned through and the second layer of skin (dermis) is damaged and is typically, a painful injury. Burns of this type cause reddening, blistering, and a mottled appearance.
particle size IOSC Incident Operations Subcommittee Approved The size of a piece of fuel, often expressed in terms of size classes.
particulate matter Fire Use Subcommittee FUSC Approved Any liquid or solid particles. "Total suspended particulates", as used in air quality, are those particles suspended in or falling through the atmosphere. They generally range in size (diameter) from 0.1 to 100 micrometers.
parts of a fire Fire Environment Committee FENC Approved Different areas of the fire usually determined by the predominant direction of fire spread and delineated from the fastest moving area (head) to the slowest moving area (base or tail). The most rapidly moving portion is designated the head of the fire, the adjoining portions of the perimeter at right angles to the head are known as the flanks, and the slowest moving portion is known as the rear or the base of the fire. 
passenger National Interagency Aviation Committee NIAC Approved Any person aboard an aircraft who does not perform the function of a flight crew member or qualified non-crew member.
passenger vehicle/motorized RV Communication, Education, and Prevention Committee CEPC In Development
passive crown fire Fire Behavior Subcommittee FBSC Approved A fire in the crowns of trees in which trees or groups of trees torch, ignited by the passing front of the fire. The torching trees reinforce the spread rate, but these fires are not basically different from surface fires.
patch burning Fire Use Subcommittee FUSC Approved Burning in patches to prepare sites for group planting or sowing or to form a barrier to subsequent fires.
patrol (person) Communication, Education, and Prevention Committee CEPC Approved A person or group of persons who carries out patrol actions.
patrol (prevention) Communication, Education, and Prevention Committee CEPC Approved To travel over a given route to prevent, detect, and suppress fires. Includes interaction with the public for wildland fire prevention and educational purposes.
patrol [suppression] Communication, Education, and Prevention Committee CEPC Approved To go back and forth vigilantly over a length of control line during and/or after construction to prevent breakovers, suppress spot fires, and extinguish overlooked hotspots.
patrol time IOSC Incident Operations Subcommittee Approved Elapsed time from completion of original mopping up until the fire is declared to be extinguished.
patrol unit IOSC Incident Operations Subcommittee Archived Any light, mobile unit with limited pumping and water capacity.
pattern IASS Interagency Aerial Supervision Subcommittee Approved The distribution of an aerially delivered retardant drop on the target area in terms of its length, width, and momentum (velocity x mass) as it approaches the ground. The latter determines the relative coverage level of the fire retardant on fuel within the pattern. 
pattern clusters Wildland Fire Investigation Subcommittee WFISC Approved A group of indicators in a close proximity, of the same or different categories, that exhibit consistent directional values.
payload National Interagency Aviation Committee NIAC Approved Weight of passengers and/or cargo being carried by an aircraft.
peak fire season Fire Environment Committee FENC Approved That period of the fire season during which fires are expected to ignite most readily, to burn with greater than average intensity, and to create damages at an unacceptable level.
peak monthly average Wildland Fire Investigation Subcommittee WFISC Approved Highest monthly average of human-caused fires calculated for a protection unit.
peak wind Fire Weather Subcommittee FWS Approved The greatest 5-second average wind speed during the previous hour that exceeded 25 knots.
peak wind direction FDSC Fire Danger Subcommittee Approved Direction at peak wind speed.
peak wind speed FDSC Fire Danger Subcommittee Approved Maximum wind speed during the previous 60 minutes.
percolation Fire Weather Subcommittee FWS Approved Passage of liquid through a porous body, as movement of water through soil.
perennial plant FDSC Fire Danger Subcommittee, Fire Use Subcommittee FUSC Approved A plant that lives for more than two growing seasons. For fire danger rating purposes, biennial plants are classed with perennial plants.
performance chart National Interagency Aviation Committee NIAC Approved A chart, table, or graph provided by the manufacturer for use in determining an aspect of helicopter and fixed-wing aircraft performance.
performance oriented objectives Incident and Position Standards Committee IPSC Archived On-the-job performance enhancement is a result of online training. Performance oriented objectives or learning objectives for this training is developed, agreed to, and tested to ensure skill transfer. The purpose of learning objectives is to define the type of learning or performance outcomes that will occur at the conclusion of instruction and how learning will be assessed. Both objectives and performance outcomes should be written as precisely as possible in order to best determine whether they have been achieved. 
perimeter access IOSC Incident Operations Subcommittee Archived Any road, trail, or route that will allow firefighting forces to reach the perimeter of a wildland fire.
perimeter date time FRSC Fire Reporting Subcommittee, Geospatial Subcommittee GSC Approved The date and time that the fire perimeter was collected (mapped).
perimeter extant Approved Identifies if a related wildland fire perimeter polygon exists for the wildland fire location point feature.
period of alert IOSC Incident Operations Subcommittee Archived Period of time when suppression crews, equipment, and aircraft are kept ready for deployment on short notice; usually employed when fire danger reaches a predetermined severity index.
permafrost Fire Weather Subcommittee FWS Approved A short term for "permanently frozen ground"; any part of the earth's crust, bedrock, or soil mantle that remains below 32° F (0° C) continuously for a number of years.
permission hierarchy Data Management Committee DMC In Development A system created to rank create, read, update, delete actions on business applications to ensure a system can only take those actions when they are considered an authoritative data source, which varies based on the state of the incident.
permission state Data Management Committee DMC Approved The authorization stage of create, read, update and delete actions in an application based on where the incident is occurring within the lifecyle.
perpendicular lane technique Wildland Fire Investigation Subcommittee WFISC Approved A search technique dividing the specific origin area into lanes that are perpendicular to the advancing fire progression for the purpose of a systematic examination.
Personal Protective Equipment (PPE) Equipment Technology Committee ETC Approved That equipment and clothing required to mitigate the risk of injury from or exposure to hazardous conditions encountered during the performance of duty. PPE includes but is not limited to: fire resistant clothing, hard hat, flight helmets, shroud, goggles, gloves, respirators, hearing protection, chainsaw chaps, and shelter. 
personnel accountability IOSC Incident Operations Subcommittee Approved The ability to account for the location and welfare of personnel, accomplished when supervisors ensure that the ICS principles and processes are functional and personnel are working within these guidelines.
personnel pool National Incident Management System Integration Committee NIMSIC Archived Personnel who have reported to the incident without an assignment (i.e., they are not assigned to an increment, strike team, or organizational unit).
pest control/deterrent/smoke out Communication, Education, and Prevention Committee CEPC In Development Fire ignited to clear vegetation as a form of pest control or as deterrent. Also used to smoke small game from burrows.
photo point Wildland Fire Investigation Subcommittee WFISC Approved The documented location where a photograph was taken.
piling and burning Fire Use Subcommittee FUSC Approved Piling slash resulting from logging or fuel management activities and subsequently burning the individual piles.
Pilot Balloon Operation (PIBAL) Fire Weather Subcommittee FWS Approved A method of determining winds aloft by periodically reading the elevation and azimuth angles of a theodolite, usually at one-minute intervals, while tracking the ascent of a small free-lift balloon. A PIBAL is commonly used for constructing a wind profile. 
pilot-in-command National Interagency Aviation Committee NIAC Approved Pilot responsible for the operation and safety of an aircraft during flight time.
pilotage National Interagency Aviation Committee NIAC Approved Navigation of aircraft by visual reference to landmarks.
pin flags Wildland Fire Investigation Subcommittee WFISC Approved Colored flags attached to metal or plastic pins to designate the location of fire pattern indicators, evidence, and other items of interest.
pin lug coupling Equipment Technology Committee ETC Approved A hose coupling with one or more cylindrical studs on its outside rim. The studs allow the use of a spanner wrench to tighten the coupling.
pincer action IOSC Incident Operations Subcommittee Approved Direct attack around a fire in opposite directions by two or more attack units. Usually conducted from the fire's tail to head.
ping-pong ball system Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Mechanized method of dispensing DAIDs (Delayed Aerial Ignition Devices) at a selected rate. The DAIDs are polystyrene balls, 1.25 inches in diameter, containing potassium permanganate. The balls are fed into a dispenser, generally mounted in a helicopter, where they are injected with a water-glycol solution and then drop through a chute leading out of the helicopter. The chemicals react thermally and ignite in 25-30 seconds. The space between ignition points on the ground is primarily a function of helicopter speed, gear ratio of the dispenser, and the number of chutes used (up to four). 
pithy stalk Wildland Fire Investigation Subcommittee WFISC Approved A vascular plant that has a usually continuous central internal stand of spongy tissue in the stem.
plan of attack IOSC Incident Operations Subcommittee Approved The selected course of action and organization of personnel and equipment in fire suppression, as applied to a particular fire or to all fires of a specific type.
planetary boundary layer Fire Weather Subcommittee FWS Approved That part of the earth's lower atmosphere that is directly influenced by the presence of the earth's surface and responds to surface forcings such as fronts, friction, evapotranspiration and convective mixing.
planimetric map Incident and Position Standards Committee IPSC Approved A map that shows the positions of features without showing the elevations of all hills and valleys of the land. It can include rivers, lakes, roads, boundaries, or other human-made symbolic features.
planning interval National Incident Management System Integration Committee NIMSIC Archived Period of time between scheduled planning meetings.
planning meeting National Incident Management System Integration Committee NIMSIC Approved The meeting which serves as a final review and approval, by the Command and General Staff, of operational plans and resources requirements. This meeting is an element of the Planning Cycle.
Planning Section National Incident Management System Integration Committee NIMSIC Approved The ICS Section that collects, evaluates, and disseminates operational information related to the incident and for the development of the IAP. This section also maintains information on the current/forecasted situation and on the status of resources assigned to the incident.
Plastic Sphere Dispenser (PSD) National Interagency Aviation Committee NIAC Approved Device installed, but jettisonable, in a helicopter, which injects glycol into a plastic sphere containing potassium permanganate, which is then expelled from the machine and aircraft. This produces an exothermic reaction resulting in ignition of fuels on the ground for prescribed or wildland fire applications. 
plow line Equipment Technology Committee ETC Approved Fireline constructed by a tractor plow.
plume Fire Use Subcommittee FUSC Approved A convection column generated by combustion (of wildland fuel).
plume rise Fire Use Subcommittee FUSC Approved How high above the level of release an emission plume rises.
plume-dominated wildland fire Fire Use Subcommittee FUSC Approved A wildland fire whose activity is determined by the convection column.
PM10 Fire Use Subcommittee FUSC Approved Particulate matter of mass median aerodynamic diameter (MMAD) less than or equal to 10 micrometers.
PM2.5 Fire Use Subcommittee FUSC Approved Particulate matter of mass median aerodynamic diameter (MMAD) less than or equal to 2.5 micrometers.
pocket weather meter Fire Weather Subcommittee FWS Approved A handheld electronic device that measures temperature, humidity, wind speed, and possibly other atmospheric variables, depending on brand and model.
pockets of a fire Fire Behavior Subcommittee FBSC Approved Unburned indentations in the fire edge formed by fingers or slow burning areas.
point date time Approved The date and time that the fire point was collected in the field.
point name Approved An additional field to assist with identifying the feature.
point of attack IOSC Incident Operations Subcommittee Approved That part of the fire on which work is started when suppression crews arrive.
point of origin Wildland Fire Investigation Subcommittee WFISC Approved The exact physical location within the Ignition Area where a heat source and the local fuel interact, resulting in a fire.
point of origin on unprotected land IFPC Interagency Fire Planning Committee Approved Point of Origin of an incident for which no fire agency has been assigned as the protecting unit.
point source Fire Use Subcommittee FUSC Approved A permanent source of air pollution that can be distinctly identified such as a smokestack.
point source fire predictions Fire Use Subcommittee FUSC Approved Predictions that apply to an initiating fire burning during a time when conditions have been relatively constant, or where it can be assumed that the fire will maintain a basically elliptical shape.
point type Approved Description of the type of point.
point/zone protection IFPC Interagency Fire Planning Committee Approved A wildfire response strategy which protects specific assets or highly valued resources from the wildfire without directly halting the continued spread of the wildfire.
poise Equipment Technology Committee ETC Approved Unit of fluid viscosity in fire retardant, defined as tangential force per unit area (dynes/square centimeter) required to maintain unit difference in velocity (1 centimeter/second) between two parallel planes separated by 1 cm of fluid (1 poise=1 dyne-second/cubic centimeter). 
polygon date time Approved The date and time that the polygon was collected in the field
portable pump Equipment Technology Committee ETC Approved Small gasoline-driven pump that can be carried to a water source by one or two firefighters or other conveyance over difficult terrain.
portatank Equipment Technology Committee ETC Approved Container, either with rigid frame or self supporting, which can be filled with water or fire chemical mixture from which fire suppression resources can be filled. It can also be a source for charging hose lays from portable pumps or stationary engines.
position code Position Naming Board PNB Approved A code (mnemonic) for designating a position used in incident management response
position currency requirement Incident and Position Standards Committee IPSC Approved The requirement to perform satisfactorily in a specified position within the last five years (three years for aviation and expanded dispatch positions) in order to maintain qualification for the position.
position performance assignment Incident and Position Standards Committee IPSC Approved An assignment in which an individual is being evaluated for tasks found in the position task book.
position qualification requirement NWCG-EB NWCG Executive Board Approved A component of NWCG standards. They enable consistent and uniform performance by personnel mobilized by position under NIMS-ICS principles. Position qualification requirements include training, experience, physical fitness, position currency and incident position descriptions (duties and responsibilities).
position qualifications National Incident Management System Integration Committee NIMSIC Approved The minimum criteria necessary for individuals to fill a specific position.
position specific standard NWCG-EB NWCG Executive Board Approved Derived from the incident position descriptions and are a component of NWCG standards. Position specific standards specify the tasks and behaviors that make up the incident position’s duties and responsibilities.
Position Steward Incident and Position Standards Committee IPSC Approved The committee or subgroup that is assigned to manage an incident position
Position Task Book (PTB) Incident and Position Standards Committee IPSC Approved A document listing the performance requirements (competencies and behaviors) for a position in a format that allows for the evaluation of individual (trainee) performance to determine if an individual is qualified in the position. Successful performance of PTB tasks, as observed and recorded by a qualified evaluator, will result in a recommendation to the trainee's home unit that the individual be certified in the position. 
position title Position Naming Board PNB Approved A title for a position used for incident management response.
positive displacement pump Equipment Technology Committee ETC Approved A pump which moves a specified quantity of water through the pump chamber with each stroke or cycle; it is capable of pumping air, and therefore is self-priming, but must have pressure relief provisions if plumbing or hoses have shut-off nozzles or valves . Gear pumps and piston pumps are common examples of this type. 
possible Wildland Fire Investigation Subcommittee WFISC Approved A level of certainty that is feasible but does not rise to the level of probable.
potato roll Equipment Technology Committee ETC Approved Quick method of rolling hose for pick up; hose is rolled as a ball of string.
Pounds per Square Inch (PSI) Equipment Technology Committee ETC Approved Measurement of pressure (e.g., pump pressure, nozzle pressure, friction loss in hose, pressure loss or gain due to elevation).
power generation/transmission/distribution Communication, Education, and Prevention Committee CEPC In Development Systems designed to produce, transport and distribute energy. (summary of information found in PMS 412 and FI-210)
pre-green FDSC Fire Danger Subcommittee Approved In the 1978 version of NFDRS, the herbaceous stage approximately 30 days prior to green-up.
preattack Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved A planned, systematic procedure for collecting, recording, and evaluating prefire and fire management intelligence data for a given planning unit or preattack block. The planning phase is usually followed by a construction and development program integrated with other resources and activities. 
preattack block Data Management Committee DMC Approved Unit of wildland delineated by logical and strategic topographic features for preattack planning.
preattack planning Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved Within designated blocks of land, planning the locations of firelines, fire camps, water sources, and helispots; planning transportation systems, probable rates of travel, and constraints of travel on various types of attack units; and determining what types of attack units likely would be needed to construct particular firelines, their probable rate of fireline construction, and topographic constraints on fireline construction. 
precautionary landing National Interagency Aviation Committee NIAC Approved A landing necessitated by apparent impending failure of engines, systems, or components which makes continued flight unadvisable.
precipitation Fire Weather Subcommittee FWS Approved the amount of water falling upon the earth as rain or in frozen form such as snow, sleet, or hail
precipitation amount FDSC Fire Danger Subcommittee Approved The total amount of precipitation that occurred within the preceding 24-hour period.
precipitation duration Fire Weather Subcommittee FWS Approved Time, in hours and fraction of hours, that a precipitation event lasts. More precisely, for fire danger rating purposes, the length of time that fuels are subjected to liquid water.
precipitation gauge Fire Weather Subcommittee FWS Approved Device commonly used to collect and permit measurement of any form of rain and snow sufficiently heavy to have fallen to the earth's surface.
precision approach procedure National Interagency Aviation Committee NIAC Approved A standard instrument approach procedure for fixed-wing aircraft in which an electronic glide slope is provided, such as ILS and PAR.
Precision Approach Radar (PAR) National Interagency Aviation Committee NIAC Approved Blind landing in which the aircraft is observed from the ground by means of radar and directed along a suitable glide path by instructions radioed to the pilot.
preconnected Equipment Technology Committee ETC Approved Hard suction hose or discharge hose carried connected to pump, eliminating delay occasioned when hose and nozzles must be connected and attached at fire.
predictive services Fire Weather Subcommittee FWS Approved Those Geographic Area and National-level fire weather or fire danger services and products produced by wildland fire agency meteorologists and intelligence staffs in support of resource allocation and prioritization.
Predictive Services Area Name Approved Unique name of the Predictive Services Area defined by Predictive Services.
Predictive Services Area national code Approved Unique code for every PSA associated to a single unit.
preignition combustion phase Fire Behavior Subcommittee FBSC Approved Thermal or chemical decomposition of fuel at an elevated temperature. This is the pre-combustion stage of burning during which distillation and pyrolysis predominate. Heat energy is absorbed by the fuel which, in turn, gives off water vapor and flammable tars, pitches, and gases. These ignite when mixed with oxygen to initiate the flaming combustion phase. 
preignition phase Fire Behavior Subcommittee FBSC Approved Preliminary phase of combustion in which fuel elements ahead of the fire are heated, causing fuels to dry. Heat induces decomposition of some components of the wood, causing release of combustible organic gases and vapors.
preparedness (activity) FDSC Fire Danger Subcommittee, IFPC Interagency Fire Planning Committee Approved Activities that lead to a safe, efficient, and cost-effective fire management program in support of land and resource management objectives through appropriate planning and coordination.
preparedness (capability) FDSC Fire Danger Subcommittee, IFPC Interagency Fire Planning Committee Approved The range of deliberate, critical tasks, and activities necessary to build, sustain, and improve the capability to protect against, respond to, and recover from domestic incidents.
preparedness (mental) FDSC Fire Danger Subcommittee, IFPC Interagency Fire Planning Committee Approved Mental readiness to recognize changes in fire danger and act promptly when action is appropriate.
preparedness level National Coordination System Committee NCSC Approved Increments of planning and organizational readiness dictated by burning conditions, fire activity, and resource availability.
preparedness plan IFPC Interagency Fire Planning Committee Approved A written plan providing for timely recognition of approaching critical fire situations, priority setting, the deployment of forces, and other actions to respond to those situations.
preparedness/preposition (event) National Coordination System Committee NCSC Approved An event dealing with effective and efficient response by the wildland fire community to planned, anticipated or event activity. This category includes activities such as move-up and cover, fire menace standby, and severity activities.
prescribed burning Fire Use Subcommittee FUSC Approved Application of prescribed fire.
prescribed fire FMB Fire Management Board Approved A wildland fire originating from a planned ignition in accordance with applicable laws, policies, and regulations to meet specific objectives.​
prescribed fire (event) National Coordination System Committee NCSC Approved An event, where a wildland fire originating from a planned ignition in accordance with applicable laws, policies, and regulations to meet specific objectives.
prescribed fire burn plan Fire Use Subcommittee FUSC Approved A plan required for each fire application ignited by management. Plans are documents prepared by qualified personnel, approved by the agency administrator, and include criteria for the conditions under which the fire will be conducted (a prescription). Plan content varies among the agencies.
prescribed fire escape indicator FRSC Fire Reporting Subcommittee Approved Indicates whether the wildfire resulted from an escaped prescribed fire. Y or N.
prescribed fire module Fire Use Subcommittee FUSC Approved A team of skilled and mobile personnel dedicated primarily to prescribed fire management that can ignite, hold and monitor prescribed fires.
prescribed fire plan Fire Use Subcommittee FUSC Approved A plan required for each fire application ignited by management. Plans are documents prepared by qualified personnel, approved by the agency administrator, and include criteria for the conditions under which the fire will be conducted (a prescription).
prescription Fire Use Subcommittee FUSC Approved In the context of wildland fire, a prescription is measurable criteria that define conditions under which a prescribed fire may be ignited. Prescriptions may also be used to guide selection of management responses to wildfire to define conditions under which management actions are most likely to achieve incident management objectives. Prescription criteria typically describe environmental conditions such as temperature, humidity and fuel moisture, but may also include safety, economic, public health, geographic, administrative, social, or legal considerations. 
pressure gradient Fire Weather Subcommittee FWS Approved The difference in atmospheric pressure between two points on a weather map. That is, the magnitude of pressure difference between two points at sea level, or at constant elevation above sea level. Wind speed is directly related to pressure gradient. If distance between constant pressure lines is reduced by one-half, wind speed will be doubled. Conversely, if distance between lines is doubled, wind speed will be reduced by one-half. 
pressure loss Equipment Technology Committee ETC Approved Reduction in water pressure between a pump or hydrant and a nozzle due to expenditure of pressure energy required to move water through a hose; includes losses due to back pressure, friction loss, elevation loss, and/or losses in fittings.
pressure pattern Fire Weather Subcommittee FWS Approved The distribution of surface atmospheric pressure features over an area of the earth as shown on a weather map. Surface pressure features include lines of constant pressure (isobars), highs, lows, and pressure gradient. The pressure pattern is directly related to wind speeds and directions at specific locations. 
presuppression IFPC Interagency Fire Planning Committee Approved Activities in advance of fire occurrence to ensure effective suppression action. Includes planning the organization, recruiting and training, procuring equipment and supplies, maintaining fire equipment and fire control improvements, and negotiating cooperative and/or mutual aid agreements. 
pretreat Equipment Technology Committee ETC Approved The use of water, foam or retardant along a control line in advance of the fire. Often used where ground cover or terrain is considered best for control action.
prevention Communication, Education, and Prevention Committee CEPC Approved Activities directed at reducing the incidence of human-caused wildfires, including public education, law enforcement, personal contact, and other actions taken to reduce ignitions.
Prevention of Significant Deterioration (PSD) Fire Use Subcommittee FUSC Approved A program identified by the Clean Air Act to prevent air quality and visibility degradation and to remedy existing visibility problems. Areas of the country are grouped into 3 classes which are allowed certain degrees of pollution depending on their uses. National Parks and Wilderness Areas meeting certain criteria are "Class I" or "clean area" in that they have the smallest allowable increment of degradation. 
prevention team Incident Business Committee IBC Approved Provides support to fire prevention and wildland fire educational needs preceding and during periods of high wildland fire danger or prescribed fire activity. The teams provide assistance to wildland fire managers with coordination of fire loss mitigation efforts with public, state or local agencies.
primary email Data Management Committee DMC Approved Individual’s primary email
primary lookout IOSC Incident Operations Subcommittee Archived A lookout point that must be staffed to meet planned minimum seen area coverage in a given locality. For that reason, continuous service is necessary during the normal fire season and the lookout (person) is not sent to fires.
primary phone Data Management Committee DMC Approved Individual’s primary phone.
primary weather station identifier PSOG National Predictive Services Oversight Group Approved The six-digit National Weather Station ID for the National Fire Danger Rating System (NFDRS) weather station that best represents the predominate weather and climate conditions for the incident site at the time of initial response.
priming Equipment Technology Committee ETC Approved Filling pump with water when pump is taking water not under a pressure head. Necessary for centrifugal pumps.
principal meridian Incident and Position Standards Committee IPSC Approved An imaginary line on the ground running north-south which is accurately laid out to serve as the reference meridian in land surveys.
probability Fire Weather Subcommittee FWS Approved A number representing the chance that a given event will occur. The range is from 0% for an impossible event, to 100% for an inevitable event.
probability forecast Fire Weather Subcommittee FWS Approved A forecast of the probability of occurrence of one or more of a mutually exclusive set of weather contingencies as distinguished from a series of categorical statements.
probability of ignition Fire Behavior Subcommittee FBSC Approved The chance that a firebrand will cause an ignition when it lands on receptive fuels.
probable Wildland Fire Investigation Subcommittee WFISC Approved A level of certainty corresponding to being more likely true than not.
procurement office Incident Business Committee IBC Approved Agency personnel with specific delegation of procurement authority, acting within the limits of agency policy of said authority.
Procurement Unit Incident Business Committee IBC Approved Functional unit within the Finance/Administration Section responsible for managing all financial matters pertaining to vendor contracts.
proficiency and currency event (event) National Coordination System Committee NCSC Approved An event dealing with maintenance of licenses, currencies, or proficiencies, including recurring proficiencies.
progressive hose lay Equipment Technology Committee ETC Approved A hose lay in which double shutoff wye (Y) valves are inserted in the main line at intervals and lateral lines are run from the wyes to the fire edge, thus permitting continuous application of water during extension of the lay.
progressive method of line construction IOSC Incident Operations Subcommittee Approved A system of organizing workers to build fireline in which they advance without changing relative positions in line.
prohibited Communication, Education, and Prevention Committee CEPC Approved Allows identification of an activity which is unlawful or otherwise prohibited (burn ban, unpermitted, etc.) by local authorities.
Project Activity Level (PAL) FDSC Fire Danger Subcommittee Approved An application of fire danger rating to support regulation of contractors involved in land management activities for fire prevention purposes in California.
project objectives IOSC Incident Operations Subcommittee Archived The specific results expected from completing a project.
projected incident activity Fire Environment Committee FENC Approved An estimate of the direction in which the incident is expected to spread, migrate, or expand within a specified time frame.
property information Approved Accountable property information to track ownership.
proportioner Equipment Technology Committee ETC Approved A device that adds a predetermined amount of foam concentrate to water to form foam solution.
protected lands IFPC Interagency Fire Planning Committee Approved Areas for which a fire protection organization has the primary responsibility for managing a wildfire and directing fire management actions. Such responsibility may be authorized by law, contract, or personal interest of the firefighting agent (e.g., a lumber operator). Note: Several agencies or entities may have some basic responsibilities (e.g., private owner) without being known as the fire organization having primary responsibility.
protected side Wildland Fire Investigation Subcommittee WFISC Approved The side of an object opposite the oncoming fire and therefore shielded from the oncoming fire by the object itself.
protecting agency Incident Business Committee IBC Approved The agency responsible for providing direct incident management and services to a given area pursuant to its jurisdictional responsibility or as specified by law, contract or agreement.
protecting unit FRSC Fire Reporting Subcommittee Approved The entity responsible for providing direct incident management and services to a given area pursuant to its jurisdictional responsibility or as specified by law, contract or agreement.
protection area (polygon) Data Management Committee DMC Approved A geographical area which is administratively defined and for which organized fire suppression activities are formally planned.
protection area (primary responsibility) Data Management Committee DMC Approved That area for which a particular fire protection organization has the primary responsibility for attacking an uncontrolled fire and for directing the suppression action. Such responsibility may develop through law, contract, or personal interest of the firefighting agent (e.g., a lumber operator). Several agencies or entities may have some basic responsibilities (e.g., private owner) without being known as the fire organization having direct protection responsibility. 
protection boundary Data Management Committee DMC Approved The exterior perimeter of an area within which a specified fire agency has assumed a degree of responsibility for wildland fire control. It may include land in addition to that for which the agency has jurisdiction or contractual responsibility.
provider unit National Coordination System Committee NCSC Approved Any government organization that is a source of resources for response or mutual aid support to an incident, whether in the field, at the scene of an incident, or operations center.  This includes government organizations that administer contracts or agreements for resources.
psychrometer Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved General name for instruments designed to determine the moisture content of air. A psychrometer consists of dry- and wet-bulb thermometers that give the dry- and wet-bulb temperatures, which in turn are used to determine relative humidity and dew point.
public aircraft National Interagency Aviation Committee NIAC Approved Aircraft used only in the service of a government or a political subdivision. It does not include any government-owned aircraft engaged in carrying persons for commercial purposes.
public assistance (event) National Coordination System Committee NCSC Approved A community or public service event, managed by an organization external to the fire community, which requires resource support from the fire community. This category includes VIP visits, law enforcement activities, concerts, conventions, parades, road/bridge closures, etc.
public service organization event (event) National Coordination System Committee NCSC Approved An event managed by local public service organizations (police, fire, law enforcement, emergency medical services, or military).
pulaski Equipment Technology Committee ETC Approved A combination chopping and trenching tool widely used in fireline construction, which combines a single-bitted axe blade with a narrow adze-like trenching blade fitted to a straight handle.
punky material Fire Use Subcommittee FUSC Approved Partly decayed material, such as old wood, in which fire can smolder unless it is carefully mopped up and extinguished. A good receptor for firebrands when dry.
pyrolysis Fire Behavior Subcommittee FBSC Approved The thermal or chemical decomposition of fuel at an elevated temperature. This is the preignition combustion phase of burning during which heat energy is absorbed by the fuel which, in turn, gives off flammable tars, pitches, and gases.
pyrotechnic Wildland Fire Investigation Subcommittee WFISC Approved A mixture of chemicals designed to produce heat, light, gas, smoke or noise.
quadrangle Geospatial Subcommittee GSC Approved Mapping unit which defines an area in terms of longitude and latitude distance. Two common scales are 1:24,000 quadrangles, which are 7.5' longitude x 7.5' latitude, and 1:62,500 quadrangles, which are 15' longitude x 15' latitude.
qualification sheet Wildland Fire Investigation Subcommittee WFISC Approved A written resume of an expert witness used to show that expert's sufficient special expertise in the field.
qualifications and certification National Incident Management System Integration Committee NIMSIC Archived This subsystem of NIIMS provides recommended qualification and certification for those personnel responding to an incident regionally or nationally, allowing for the development of local minimum standards to meet local needs. Standards typically include training, experience, and physical fitness.
qualified non-crew member National Interagency Aviation Committee NIAC Approved An individual, other than a member of the crew, aboard an aircraft whose presence is required to perform, or is associated with the performance of, a governmental function.
qualitative risk assessment WMSC WUI Mitigation Subcommittee Archived Qualitative risk assessment is the application of judgment based in knowledge and experience when assessing wildfire risk, the potential for ignitions and recommendations regarding possible ways to mitigate the risk.
quantitative risk assessment WMSC WUI Mitigation Subcommittee Archived Quantitative risk assessments provide a method by which we can calculate risk based on measurements or estimates of various risk components such as likelihood of fire occurrence, intensity of fire should it occur, and susceptibility to fire of the various values being evaluated.
radial National Interagency Aviation Committee NIAC Approved A magnetic bearing extending from a ground-based navigational system, providing airborne navigation information.
radiant burn Risk Management Committee RMC Approved A thermal trauma that maybe a superficial, partial thickness or full thickness burn.
radiant heat flux Fire Behavior Subcommittee FBSC Approved The amount of heat flowing through a given area in a given time, usually expressed as calories/square centimeter/second.
radiation (energy) Fire Behavior Subcommittee FBSC Approved Propagation of energy in free space by virtue of joint, undulatory variations in the electric or magnetic fields in space, (i.e., by electromagnetic waves).
radiation (heat) Fire Behavior Subcommittee FBSC Approved Transfer of heat in straight lines through a gas or vacuum other than by heating of the intervening space.
radio cache Equipment Technology Committee ETC Approved A cache may consist of a number of portable radios, base station, and, in some caches, a radio repeater that is stored in a predetermined location for dispatch to incidents.
radio fix National Interagency Aviation Committee NIAC Approved Determination of position by one or more radio navigational aids.
radioactive/nuclear conditions (event) National Coordination System Committee NCSC Approved An event dealing with the various situations that arise as a result of the presence of radioactive materials.
radiosonde Fire Weather Subcommittee FWS Approved A device carried aloft by a balloon equipped with measuring instruments that automatically convert temperature, pressure, and humidity data into electrical impulses and transmit this information to a ground recorder.
rail accident (event) National Coordination System Committee NCSC Approved An event dealing with an accident or mishap involving railway vehicles.
rail grinding Communication, Education, and Prevention Committee CEPC In Development Process usually done with a maintenance of way vehicle or train to restore the profile and remove irregularities from worn tracks.
railroad fire Communication, Education, and Prevention Committee CEPC, Wildland Fire Investigation Subcommittee WFISC Approved A fire resulting from any operation or activity of a railroad, except smoking.
railroad operations and maintenance Communication, Education, and Prevention Committee CEPC In Development
range fire IOSC Incident Operations Subcommittee Approved Any wildfire on rangeland.
rappelling Interagency Helicopter Operations Subcommittee IHOPS Approved Technique of landing specifically trained and certified firefighters from hovering helicopters; involves sliding down ropes with the aid of friction-producing devices.
rate of spread Fire Behavior Subcommittee FBSC Approved The relative activity of a fire in extending its horizontal dimensions. It is expressed as rate of increase of the total perimeter of the fire, as rate of forward spread of the fire front, or as rate of increase in area, depending on the intended use of the information. Usually it is expressed in chains or acres per hour for a specific period in the fire's history.
rate of spread factor Fire Behavior Subcommittee FBSC Approved A factor usually on a scale of 1 to 100 which represents a relative rate of forward spread for a specific fuel condition and fixed weather conditions (or fuel model). Factors can be used as multipliers, arguments for entering tables, or provide a ratio of values between two fuels. 
rate of spread meter Fire Behavior Subcommittee FBSC Approved A device that computes the probable rate of spread of a fire for different combinations of fuel moisture, wind speed, and other selected factors.
rating period FDSC Fire Danger Subcommittee Approved The period of time during which a fire danger rating value is considered valid or representative for administrative or other purposes. Normally it is 24 hours extending from midnight to midnight.
rawinsonde Fire Weather Subcommittee FWS Approved Method of upper-air observation consisting of an evaluation of the wind speed and wind direction, temperature, pressure, and relative humidity aloft by means of a balloon-borne radiosonde tracked by a radar or radio direction-finder.
re-certification Incident and Position Standards Committee IPSC Approved Confirmation through the re-issuance of an incident qualification card that an individual has regained qualifications for a specified position that was lost through a lack of current experience. A key component in the certification or re-certification process is the subjective evaluation by the appropriate agency official of an individual's capability to perform in a position. 
reaction intensity Fire Weather Subcommittee FWS Approved The rate of heat release, per unit area of the flaming fire front, expressed as heat energy/area/time, such as Btu/square foot/minute, or Kcal/square meter/second.
readiness (fire) IOSC Incident Operations Subcommittee Approved Condition or degree of being completely ready to cope with a potential fire situation.
readiness (mental) IOSC Incident Operations Subcommittee Approved Mental readiness to recognize changes in fire danger and act promptly when action is appropriate.
rear (of a fire) (fire spread) Fire Behavior Subcommittee FBSC Approved That portion of a fire spreading directly into the wind or down slope.
rear (of a fire) (opposite the head) Fire Behavior Subcommittee FBSC Approved That portion of a fire edge opposite the head.
rear (of a fire) (slowest spreading) Fire Behavior Subcommittee FBSC Approved Slowest spreading portion of a fire edge.
reason for responding to incident on unprotected land IFPC Interagency Fire Planning Committee Approved The rationale an agency responded to an incident where the point of origin is on unprotected land.
Reasonably Available Control Measures (RACM) Fire Use Subcommittee FUSC Approved Control measures developed by EPA which apply to residential wood combustion, fugitive dust, and prescribed and silvicultural burning in and around "moderate" PM-10 non-attainment areas. RACM is designed to bring an area back into attainment and uses a smoke management program which relies on weather forecasts for burn/no-burn days. 
reassigned (at incident) Proposed New A resource on a filled request has been reassigned from one incident to the another, but the mobilization travel has not started.
reburn (historical) IOSC Incident Operations Subcommittee Approved An area that has reburned.
reburn (leftover fuel) IOSC Incident Operations Subcommittee Approved Repeat burning of an area over which a fire has previously passed, but left fuel that later ignites when burning conditions are more favorable.
Reconnaissance (RECON) IOSC Incident Operations Subcommittee, National Interagency Aviation Committee NIAC Approved To examine a fire area to obtain information about current and probable fire behavior and other related fire suppression information.
recorders National Incident Management System Integration Committee NIMSIC Archived Individuals within ICS organizational units who are responsible for recording information. Recorders may be found in planning, logistics and finance/administration units.
recovery (increased relative humidity) Fire Weather Subcommittee FWS Approved The increase in fuel moisture as a result of increased relative humidity, usually occurring overnight.
recovery (relative humidity) Fire Weather Subcommittee FWS Approved The general term used to describe the maximum overnight value of atmospheric relative humidity.
recreation and ceremony Communication, Education, and Prevention Committee CEPC In Development
recreation fire Wildland Fire Investigation Subcommittee WFISC Approved A fire resulting from recreational use, except smoking.
recurrent training Incident and Position Standards Committee IPSC Approved Training scheduled at established intervals that has been identified as required training in order to maintain position currency.
red flag warning Fire Weather Subcommittee FWS Approved Term used by fire weather forecasters to alert forecast users to an ongoing or imminent critical fire weather pattern.
reel Equipment Technology Committee ETC Approved A frame on which hose is wound, now chiefly used for "booster" or small hose (3/4- or l-inch hose) (19 or 25 mm) supplied by a water tank on the apparatus; also, a hand-drawn 2-wheel frame for 2-1/2 inch (64 mm) hose used in industrial plants.
reference point(s) Wildland Fire Investigation Subcommittee WFISC Approved A fixed location(s) used in correlation with field measurements to document spatial relationships between items of interest at the scene.
refraction/magnification An ignition that occurs as the result of concave glass or reflective materials focusing sunlight creating intense heat.
regional haze Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved Visibility impairment caused by the cumulative air pollutant emissions from numerous sources over a wide geographic area.
regular government employee Incident Business Committee IBC Approved Includes any individual hired under authorities other than the AD Pay Plan for Emergency Workers. Federal general schedule and federal wage system employees are included in this category.
rehabilitation IFPC Interagency Fire Planning Committee Approved Efforts undertaken within three years of a wildland fire to repair or improve fire damaged lands unlikely to recover to a management approved conditions or to repair or replace minor facilities damaged by fire.
rekindle Communication, Education, and Prevention Committee CEPC Approved Re-ignition due to latent heat, sparks, or embers or due to presence of smoke or steam.
Relative Greenness (RG) FDSC Fire Danger Subcommittee Approved An NDVI-derived image of vegetation greenness compared to how green it has been historically.
Relative Humidity (RH) Fire Weather Subcommittee FWS Approved The ratio of the amount of moisture in the air, to the maximum amount of moisture that air would contain if it were saturated. The ratio of the actual vapor pressure to the saturated vapor pressure.
relay Equipment Technology Committee ETC Approved Use of two or more fire pumps to move water a distance which would require excessive pressures in order to overcome friction loss if only one pump were employed at the source.
relay tank Equipment Technology Committee ETC Approved A tank, usually collapsible, used as a reservoir in the relay of water from one fire pump to another.
release order National Incident Management System Integration Committee NIMSIC Archived The order that defines when personnel and/or equipment will be ready for release from an incident.
released (at incident) Proposed New A resource on a filled request has been released, but the demobilization travel has not started.
relief valve Equipment Technology Committee ETC Approved A pressure-controlled device which bypasses water at a fire pump to prevent excessive pressures when a nozzle is shut down.
reload base IABS Interagency Airtanker Base Subcommittee Approved An airfield where airtankers are reloaded but not permanently stationed.
Remote Automatic Weather Station (RAWS) Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved A weather station that transmits weather observations via GOES satellite to the Wildland Fire Management Information system.
repair status Approved Status of the Suppression Repair project for each feature.
repeater National Coordination System Committee NCSC Approved A radio signal station that automatically relays a radio transmission, sometimes over a different frequency, thereby increasing the range of transmission. Repeaters are often named for the mountaintops or peaks where they are installed.
report time (resources) Wildland Fire Investigation Subcommittee WFISC Approved Elapsed time from fire discovery until the first personnel charged with initiating action for fire suppression are notified of its existence and location.
reportable fire Wildland Fire Investigation Subcommittee WFISC Approved Any wildfire that requires fire suppression to protect natural resources or values associated with natural resources, or is destructive to natural resources.
reporting locations Incident and Position Standards Committee IPSC Approved Location or facilities where incoming resources can check-in at the incident. Check-in locations include: incident command post (resources unit), incident base, camps, staging areas, helibases, helispots, and direct to the line. Check-in at one location only. 
reporting unit FRSC Fire Reporting Subcommittee Approved The entity submitting a given incident report.
Representative Fraction (RF) Incident and Position Standards Committee IPSC Approved A scale that expresses the ratio of the map distance to the ground distance in 'SAME' units of measurements. It is usually written as a fraction or ratio.
request number Incident Business Committee IBC Approved As resources are ordered to respond to an incident, Request Numbers (occasionally referred to as a resource order number) are issued. The order number includes the incident number, an alpha character (S = Supplies, E = Equipment, O = Overhead, A = Aircraft, C = Crews, M = Agency Provided Medical Care) followed by a sequential number.
required experience Incident and Position Standards Committee IPSC Approved Documented, satisfactory performance in a specified position needed to qualify for another (usually higher level) position. Required experience cannot be challenged.
required training Incident and Position Standards Committee IPSC Approved A course or courses that must be completed prior to initiating a position task book. Training which has been identified as required cannot be challenged; an agency equivalent course may be used as a substitute when the course meets or exceeds a required course's learning and performance objectives. 
rescue Risk Management Committee RMC Approved Saving a life from fire or accident; removing a victim from an untenable or unhealthy atmosphere.
rescue medical Risk Management Committee RMC Approved Any staffed ground vehicle capable of providing medical services.
rescue medical vehicle Risk Management Committee RMC Approved Any staffed ground vehicle capable of providing emergency medical care and staffed with appropriate number of trained personnel and equipment for that incident.
reserve IOSC Incident Operations Subcommittee Archived In wildland fire suppression terminology resources not assigned to a specific task, but available for assignment.
reserved Proposed New The resource has been assigned to a request but has not started travel. Either no travel has been assigned, or if travel has been assigned, the ETD has not yet passed.
residence time Fire Weather Subcommittee FWS Approved The time, in seconds, required for the flaming front of a fire to pass a stationary point at the surface of the fuel. The total length of time that the flaming front of the fire occupies one point.
residences destroyed quantity FRSC Fire Reporting Subcommittee Approved The total number of residences destroyed, or damaged to an extent requiring rebuilding, as a result of the fire. Residence is defined as a place where one lives; a house, apartment, or other shelter used as the residence of a person, family or household. This includes primary and secondary residences.
residences threatened quantity FRSC Fire Reporting Subcommittee Approved The total number of residences threatened by the fire. Residence is defined as a place where one lives; a house, apartment, or other shelter used as the residence of a person, family or household. This includes primary and secondary residences. Residences are threatened if they are at risk of loss or damage, or endangered during the course of the fire. This includes, but is not limited to, residences subject to mandatory evacuation.
residual combustion stage Fire Use Subcommittee FUSC Approved The smoldering zone behind the zone of an advancing fire front.
residual smoke Fire Use Subcommittee FUSC Approved Smoke produced by smoldering material. The flux of smoke originating well after the active flaming combustion period with little or no vertical buoyancy and, therefore, most susceptible to subsidence inversions and down-valley flows.
resilience WMSC WUI Mitigation Subcommittee Approved In general, the ability of a system (ecological or human) to resist damage and recover from a disturbance. In ecology, resilience refers to the ability of the system to return to the pre-disturbed state with no assessment of whether that state is desirable or not. From a social perspective, resilience references the ability to return to the original state but also refers to the ability to recover to a state more likely to resist or recover quickly from future disturbances.
resiliency WMSC WUI Mitigation Subcommittee Archived At a general level used to refer to the ability of a system (ecological or human) to resist damage and recover from a disturbance. In ecology, resiliency tends to refer to the ability of the system to return to the pre disturbance state with no assessment of whether that state is desirable or not. From a social perspective, resilience may reference ability to return to the original state but also can refer to the ability to recover to a state more likely to resist or recover quickly from future disturbance.
resistance to control IOSC Incident Operations Subcommittee Approved The relative difficulty of constructing and holding a control line as affected by resistance to line construction and by fire behavior.
resistance to line construction IOSC Incident Operations Subcommittee Approved The relative difficulty of constructing control line as determined by the fuel, topography, and soil.
resource capability National Coordination System Committee NCSC Approved The ability of the wildland fire program to respond to current and anticipated workload needs for the area of concern.
resource capacity IOSC Incident Operations Subcommittee, Incident and Position Standards Committee IPSC Approved The competency level in which the overhead resource is qualified to perform a position. May also be used to define how the resource performed on a specific incident. In both cases the capacity is defined as “trainee” or “qualified”.
resource order Incident Business Committee IBC Approved The form used by dispatchers, service personnel, and logistics coordinators to document the request, ordering or release of resources, and the tracking of those resources on an incident.
resource program (internal) (event) National Coordination System Committee NCSC Approved An event dealing with agency-specific non-fire program(s), such as forestry, mining, wildlife, fisheries, recreation, etc. Includes mechanical fuel treatment, timber operations, aerial bug-spraying projects, Rainbow gatherings, etc.
resource provider UIB Unit Identifier Board Approved An organizational unit with no jurisdictional authority or responsibilities but has resources to support the interagency incident management community.
resource quantity current as of date time National Coordination System Committee NCSC Approved The date and time that reflects the period for which the resource counts are current.
Resource Status Board IOSC Incident Operations Subcommittee Archived Visual aid containing pertinent information regarding fire organization, current operational period resources, previous operational period resources, and next operational period resources being prepared; placed at a convenient location in fire camp for review by fireline overhead personnel on large fires. 
Resource System of Record (RSOR) National Coordination System Committee NCSC Approved The exchange username of the system that currently is the System of Record for the resource and the capabilities for that resource.
resource tracking National Incident Management System Integration Committee NIMSIC Approved The process that all incident personnel and equipment from associated organizations use to maintain information regarding the location and status of resources ordered for or assigned to an incident.
resource value-at-risk IOSC Incident Operations Subcommittee Archived Fire suppression planning tool providing a relative expression (in five classes) of fire effects on all resources (not the value of the resources themselves).
resources (natural) IFPC Interagency Fire Planning Committee Approved The natural resources of an area, such as timber, grass, watershed values, recreation values, and wildlife habitat.
resources [incident] National Incident Management System Integration Committee NIMSIC, IFPC Interagency Fire Planning Committee Approved Personnel and equipment available or potentially available for assignment to incident operations and for which status is maintained. Resources are described by kind and type.
Resources Unit National Incident Management System Integration Committee NIMSIC Approved Resources Unit staff track the location and status of all resources assigned to an incident. They ensure all assigned resources have checked in at the incident.
respirator Equipment Technology Committee ETC, Risk Management Committee RMC Approved A device that is designed to protect the wearer from the adverse effects of inhalation hazards by removing contaminants from the surrounding air or by supplying clean air from a safe source.
responding unit Data Management Committee DMC Approved Administrative entity that provides resources in response to the incident.
responsible agency unit identifier (Point of Origin) (POO) Approved The unit identifier for the agency that has primary protection responsibility at the point of origin at the time of the incident.
responsible fire agency wfnwcgorg:ICSC Approved Agency with primary responsibility for fire suppression on any particular land area.
restricted airspace National Interagency Aviation Committee NIAC Approved Airspace of defined dimensions identified by an area on the surface of the earth within the flight of an aircraft, which is subject to restrictions (but not wholly prohibited).
restricted category National Interagency Aviation Committee NIAC Approved Aircraft that is generally used for cargo, retardant dropping, agricultural operations, survey work and other specific projects, and may not transport passengers.
restrictions Communication, Education, and Prevention Committee CEPC Approved Measures taken by jurisdictional agencies to impose bans and standards of use on certain human activities that could lead to the cause of wildland fire. Restrictions may be applied to: smoking in designated areas; open flame; mechanical operations in high-risk areas; and off-road use.
retardant (fire) Equipment Technology Committee ETC Approved A substance or chemical agent which reduces the flammability of combustibles.
retardant base National Interagency Aviation Committee NIAC Approved Ground facilities for mixing, storing, and loading fire retardant into airtankers.
retardant coverage Equipment Technology Committee ETC Approved Area of fuel covered and degree of coverage on the fuel by a fire retardant, usually expressed in terms of gallons per hundred square feet (liters per square meter).
retardant drop National Interagency Aviation Committee NIAC Approved Fire retardant cascaded from an airtanker or helitanker.
return and hold National Interagency Aviation Committee NIAC Approved An order to an airtanker pilot to return to the retardant base and await further instructions; mission completed, further loads not required.
returned from assignment Proposed New The resource has returned from the assignment but is not yet available for dispatch.
Reversible Siamese (SIMWYE) Equipment Technology Committee ETC Approved Hose fitting that performs the functions of a Siamese or a wye (i.e., to combine the flow from two lines into a single line or to permit two lines to be taken from a single line).
Rheologic properties Equipment Technology Committee ETC Approved Flow characteristics of liquid fire retardants, especially their cohesiveness or ability to hold together while falling through the air.
Rheology Equipment Technology Committee ETC Approved Science of deformation and flow of fire retardants and other liquids, especially of the cohesiveness bodies and stress-strain relationship of their particles.
rich tool Equipment Technology Committee ETC Approved A long-handled combination rake and cutting tool, the blade of which is constructed of a single row of mowing machine cutter teeth fastened to a piece of angle iron.
ridge (topographic) Incident and Position Standards Committee IPSC Approved A long narrow elevation of land; a steep slope or similar range of hills or mountains.
ridge (weather) Fire Weather Subcommittee FWS Approved An elongated area of relatively high atmospheric pressure extending from the center of a high-pressure region.
right angle transect Wildland Fire Investigation Subcommittee WFISC Approved A method to document a fire scene using right angle measurements off of a base line.
right-of-way clearing Communication, Education, and Prevention Committee CEPC In Development Use of fire to clear vegetation, debris and brush within a right-of-way.
right-of-way vegetation maintenance Communication, Education, and Prevention Committee CEPC In Development RR: Process of treating or removing flamable vegetation from the Railroad Right-of-Way (ROW). Debris/open burning: Use of fire to clear vegetation, debris and brush within a right-of-way.
ring fire Fire Use Subcommittee FUSC Approved A fire started by igniting the full perimeter of the intended burn area so that the ensuing fire fronts converge toward the center of the burn. Set around the outer perimeter of a resource to establish a protective black-line-buffer.
risk (agent) Incident and Position Standards Committee IPSC, Fire Use Subcommittee FUSC Approved A causative agent.
risk (fire danger) Incident and Position Standards Committee IPSC, Fire Use Subcommittee FUSC Approved A number related to the potential of firebrands to which a given area will be exposed during the rating day.
risk (harm or loss) Incident and Position Standards Committee IPSC, Fire Use Subcommittee FUSC Approved A chance of suffering harm or loss.
risk (ignition) Incident and Position Standards Committee IPSC, Fire Use Subcommittee FUSC Approved The chance of fire starting as determined by the presence and activity of causative agents.
risk assessment (fire planning) IFPC Interagency Fire Planning Committee Proposed New An appraisal of the interaction of hazard, exposure, and effects to a given set of values in a given area.
risk assessment (WUI) WMSC WUI Mitigation Subcommittee Approved Systematic process to comprehend the nature of risk, express and evaluate risk, with the available knowledge.
risk index FDSC Fire Danger Subcommittee Approved A number related to the probability of a firebrand igniting a fire.
Risk Management (RM) Risk Management Committee RMC Approved A continuous, five-step process that provides a systematic method for identifying and managing the risks associated with any operation.
risk source Wildland Fire Investigation Subcommittee WFISC Approved Identifiable human activity that historically has been a major cause of wildfires on a protection unit; one of the eight general causes listed on the standard fire report.
risk source ratio Wildland Fire Investigation Subcommittee WFISC Approved Portion of human-caused fires that have occurred on a protection unit chargeable to a specific risk source; calculated for each day of the week for each risk source.
rocker lug coupling Equipment Technology Committee ETC Approved Hose coupling in which the lugs used for tightening or loosening are semicircular in shape and designed to pass over obstructions.
roll cloud Fire Weather Subcommittee FWS Approved A turbulent altocumulus-type cloud formation found in the lee of some large mountain barriers. The air in the cloud rotates around an axis parallel to the range. Also sometimes refers to part of the cloud base along the leading edge of a cumulonimbus cloud; it is formed by rolling action in the wind shear region between cool downdrafts within the cloud and warm updrafts outside the cloud.
rotor National Interagency Aviation Committee NIAC Approved Assembly of airfoils (rotor blades), together with a hub and attachments, that rotates about an axis to provide lift and/or thrust on a helicopter.
rotor blast Interagency Helicopter Operations Subcommittee IHOPS Approved Air turbulence occurring under and around the main rotor of an operating helicopter.
rotor diameter National Interagency Aviation Committee NIAC Approved The main rotor arc in feet and inches (meters). Used for planning helispot clearance.
rough Fire Use Subcommittee FUSC Approved The accumulation of living and dead ground and understory vegetation, especially grasses, forest litter, and draped dead needles, sometimes with addition of underbrush such as palmetto, gallberry, and wax myrtle. Most often used for southern pine types.
rough reduction Fire Use Subcommittee FUSC Approved Reduction of fire hazard in rough, usually by prescribed burning.
run (of a fire) Fire Behavior Subcommittee FBSC Approved Rapid advance of the head of a fire, characterized by a marked transition in fireline intensity and rate of spread with respect to that noted before and after the advance.
running fire Fire Behavior Subcommittee FBSC Approved Behavior of a fire spreading rapidly with a well defined head.
rural WMSC WUI Mitigation Subcommittee Archived Any area wherein residences and other developments are scattered and intermingled with forest, range, or farm land and native vegetation or cultivated crops.
Rural Fire District (RFD) Incident Business Committee IBC Approved An organization established to provide fire protection to a designated geographic area outside of areas under municipal fire protection. Usually has some taxing authority and officials may be appointed or elected.
rural fire protection IOSC Incident Operations Subcommittee Approved Fire protection and firefighting problems that are outside of areas under municipal fire prevention and building regulations and that are usually remote from public water supplies.
saddle (topographic) Fire Environment Committee FENC Approved Depression or pass in a ridgeline.
SAFENET Risk Management Committee RMC Approved A form and process, used by wildland firefighting agencies, for reporting and resolving incidents relating to firefighter safety. The information collected is used to determine long-term trends and problem areas within the wildland fire industry.
Safety Advisory Risk Management Committee RMC Archived A safety alert addressing wildland fire safety information that isn't related to imminent or potential threats of injury.
Safety Alert Risk Management Committee RMC Archived A warning or alert concerning critical information relating to firefighter safety, that is distributed via email through an NWCG mail server. There are three types of alerts: Safety Warning, Safety Advisory, and Safety Bulletin.
safety briefing Risk Management Committee RMC Approved A safety briefing emphasizes key safety concerns on the incident and is presented at each briefing session. The safety briefing should contain information to alert incident personnel of potential risk/hazard considered to be most critical.
Safety Bulletin Risk Management Committee RMC Archived A safety alert containing a factual confirmation of a serious wildland fire accident, incident or fatality.
safety circle National Interagency Aviation Committee NIAC Approved An obstruction-free circle around the (helicopter) landing pad.
Safety Warning Risk Management Committee RMC Approved A time-sensitive alert to the wildland fire community addressing wildland fire safety hazards that pose an imminent threat, or have potential to pose a threat, to life or property.  Red hash-marked bordered stationary will be associated with this type of alert.
safety zone Risk Management Committee RMC Approved An area cleared of flammable materials used for escape in the event the line is outflanked or in case a spot fire causes fuels outside the control line to render the line unsafe. In firing operations, crews progress so as to maintain a safety zone close at hand allowing the fuels inside the control line to be consumed before going ahead. Safety zones may also be constructed as integral parts of fuel breaks; they are greatly enlarged areas which can be used with relative safety by firefighters and their equipment in the event of blowup in the vicinity. 
salvo National Interagency Aviation Committee NIAC Approved Dropping by an airtanker of its entire load of fire retardant at one time.
salvo drop National Interagency Aviation Committee NIAC Approved Total retardant or water load dropped all at once. Usually done to knock down a hotspot.
sample Fire Weather Subcommittee FWS Approved Part of a population; that portion of the population that is measured.
sample size Fire Weather Subcommittee FWS Approved The number of items or observations in a sample; usually denoted by lower case letter n.
Sand Table Exercise (STEX) Leadership Committee LC Approved A tactical decision game that employs a three-dimensional terrain model made from sand and various props to provide a visual representation of the situation described in the tactical decision game.
scope of practice Risk Management Committee RMC Approved The set of responsibilities and ethical considerations that define the extent or limits of the care provider within the current standards of practice.
scorch height Fire Use Subcommittee FUSC Approved Average heights of foliage browning or bole blackening caused by a fire.
scratch line IOSC Incident Operations Subcommittee Approved An unfinished preliminary control line hastily established or constructed as an emergency measure to check the spread of fire.
scrubbing Equipment Technology Committee ETC Approved The process of agitating foam solution and air within a confined space (usually a hose) that produces tiny, uniform bubbles - the length and type of hose determine the amount of scrubbing and, therefore, foam quality.
sea breeze Fire Weather Subcommittee FWS Approved A breeze (wind) blowing inland from the sea generally during daytime hours.
sea-level pressure Fire Weather Subcommittee FWS Approved Pressure value obtained by the theoretical reduction or increase of station pressure to sea level. The average atmospheric pressure at sea level is 14.7 psi.
search/rescue/recovery (event) National Coordination System Committee NCSC Approved An event, usually managed by organizatons external to the fire community, for which the primary focus is the search, rescue and/or recovery of people or things. This category includes missing persons, entrapments, etc.
season code FDSC Fire Danger Subcommittee Approved One of four designations of seasonal plant development used in the 1988 version of NFDRS.
seasonal monthly average Fire Weather Subcommittee FWS Approved Historically, the average number of human-caused fires occurring on a protection unit per month during the established fire season.
seasonal risk class Wildland Fire Investigation Subcommittee WFISC Approved Objective ranking of protection units within an administrative group based on the number of human-caused fires for at least the past five years.
Second Order Fire Effects (SOFE) Fire Use Subcommittee FUSC Approved The secondary effects of fire such as tree regeneration, plant succession, and changes in site productivity. Although second order fire effects are dependent, in part, on first order fire effects, they also involve interaction with many other non-fire variables. 
second-degree burn Risk Management Committee RMC Approved A burn in which the skin is blistered.
second-in-command National Interagency Aviation Committee NIAC Approved Pilot who is designated to be second-in-command of an aircraft during flight time.
secondary line IOSC Incident Operations Subcommittee Approved Any fireline constructed at a distance from the fire perimeter concurrently with or after a line already constructed on or near to the perimeter of the fire. Generally constructed as an insurance measure in case the fire escapes control by the primary line. 
secondary lookout (location) IOSC Incident Operations Subcommittee Approved A lookout point intermittently used to supplement the visible area coverage of the primary lookout system when required by fire danger, poor visibility, or other factors.
secondary lookout (person) IOSC Incident Operations Subcommittee Approved The person who occupies such a station.
secondary phone Data Management Committee DMC Approved Individual’s secondary phone.
secondary weather station Fire Weather Subcommittee FWS Approved Station at which minimum weather measurements are taken to compute ratings of burning conditions; provides supplementary information on weather experience.
section National Incident Management System Integration Committee NIMSIC Approved The ICS organizational level having responsibility for a major functional area of incident management (e.g., Operations, Planning, Logistics, and Finance/Administration).
section area Incident and Position Standards Committee IPSC Approved An area of land one mile square and containing 640 acres, more or less, which is one of 36 parts of a township.
security weather watch IOSC Incident Operations Subcommittee Archived Observers are posted at one or more strategic locations in the proximity of a fire to detect and warn fire personnel of pending critical weather changes that might significantly affect the fire.
segment IOSC Incident Operations Subcommittee Approved A geographical area in which a task force/strike team leader or supervisor of a single resource is assigned authority and responsibility for the coordination of resources and implementation of planned tactics. A segment may be a portion of a division or an area inside or outside the perimeter of an incident. Segments are identified with Arabic numbers, i.e., A-1, etc. and are not to be used as radio designators. 
selection area National Coordination System Committee NCSC Approved Indicates the dispatch center inside/outside the current dispatch center for which resources are being requested.
Self-Contained Breathing Apparatus (SCBA) Risk Management Committee RMC Approved Portable air (not oxygen) tanks with regulators which allow firefighters to breathe while in toxic smoke conditions. Usually rated for 30 minutes of service. Used primarily on fires involving structures or hazardous materials.
separation (aircraft) IASS Interagency Aerial Supervision Subcommittee Approved The horizontal and vertical spacing of aircraft working over or near a wildfire or other incident.
separation (airports) IASS Interagency Aerial Supervision Subcommittee Approved Spacing of aircraft while landing and taking off at airports to achieve safe and orderly movement in flight.
separation (personnel) IOSC Incident Operations Subcommittee Approved Spacing of personnel while performing line construction activities.
serial number National Coordination System Committee NCSC Approved A set of numbers that is put on equipment by the manufacturer so that each has a different number and can be recognized.
Serious Accident Investigation Team (SAIT) Risk Management Committee RMC Approved A formal investigation team that is organized with the purpose of conducting an accident investigation for an occurred serious accident. The team is given full authorization to conduct the investigation from involved agencies through letter of delegation. 
serious aircraft incident National Interagency Aviation Committee NIAC Approved An incident or malfunction that could adversely affect the safety of flight.
Service Branch National Incident Management System Integration Committee NIMSIC Approved A branch within the logistics section responsible for service activities at the incident. Includes the communications, medical and food units.
set (incendiary) Wildland Fire Investigation Subcommittee WFISC Approved An individual incendiary fire.
set (individual) Wildland Fire Investigation Subcommittee WFISC Approved Individual lightning or railroad fires, especially when several are started within a short time.
set (material) Wildland Fire Investigation Subcommittee WFISC Approved Material left to ignite an incendiary fire at a later time.
set (planned) Wildland Fire Investigation Subcommittee WFISC Approved Burning material at the points deliberately ignited for backfiring, slash burning, prescribed burning, and other purposes.
set (point of origin) Wildland Fire Investigation Subcommittee WFISC Approved The point or points of origin of an incendiary fire.
severe winter weather (event) Approved An event dealing with response to severe winter weather such as blizzards, heavy snow, or ice storms.
severity Fire Use Subcommittee FUSC Approved See fire severity
severity funding Incident Business Committee IBC Approved Suppression funds used to increase the level of presuppression capability and fire preparedness when predicted or actual burning conditions exceed those normally expected, due to severe weather conditions.
severity index FDSC Fire Danger Subcommittee Approved A number that indicates the relative net effects of daily fire danger on the fire load for an area during a specified period, such as a fire season.
shaded fuel break Fire Use Subcommittee FUSC Approved Fuel breaks built in timbered areas where the trees on the break are thinned and pruned to reduce the fire potential yet retain enough crown canopy to make a less favorable microclimate for surface fires.
Shareable Content Object (SCO) Incident and Position Standards Committee IPSC Archived Self-contained units of learning. They can be used as building blocks (or legos) to create packages (lessons) of SCOs, but they cannot be broken down into smaller units.
Shareable Content Object Re-usable Model (SCORM) Incident and Position Standards Committee IPSC Archived A specification for standardizing the reusability and interoperability of learning content. SCORM has been developed by the Advanced Distributed Learning initiative (ADL). SCORM focuses on two critical pieces of learning content interoperability: It defines an aggregation model for packaging learning content. It defines an API for enabling communications between learning content and the system that launches it.
shock wave Wildland Fire Investigation Subcommittee WFISC Approved The leading edge of an expanding air mass.
Short Takeoff or Landing (STOL) Airstrip National Interagency Aviation Committee NIAC Approved Developed or undeveloped area that has been tested and will accommodate STOL aircraft.
Short Takeoff or Landing Aircraft National Interagency Aviation Committee NIAC Approved An aircraft which has the capability of operating from a STOL runway in accordance with applicable airworthiness and operating regulations.
short-range spotting Fire Use Subcommittee FUSC Approved Firebrands, flaming sparks, or embers are carried by surface winds, starting new fires beyond the zone of direct ignition by the main fire. The range of such spotting is usually less than 1/4 mile.
short-term Incident Business Committee IBC Approved Persons or work for which employment is less than 12 months (excluding firefighters hired for a particular fire).
short-term fire retardant Equipment Technology Committee ETC Approved Fire retardant that inhibits combustion primarily by the cooling and smothering action of water. Chemicals may be added to the water to alter its viscosity or retard its evaporation, thereby increasing its effectiveness.
shoulder carry Equipment Technology Committee ETC Approved Method of carrying hose on the shoulders.
shrub Fire Use Subcommittee FUSC Approved A woody perennial plant differing from a perennial herb by its persistent and woody stem; and from a tree by its low stature and habit of branching from the base.
shrub type FDSC Fire Danger Subcommittee Approved The two-category (evergreen, deciduous) classification of shrubs vegetation in the 1988 version of NFDRS.
shutoff nozzle Equipment Technology Committee ETC Approved Common type of fire hose nozzle permitting stream flow to be controlled by the firefighter at the nozzle rather than only at the source of supply.
shutoff pressure Equipment Technology Committee ETC Approved Maximum pressure a centrifugal pump will attain when water flow is clamped or shut off.
Siamese Equipment Technology Committee ETC Approved Hose fitting (preferably gated) for combining flow from two or more lines of hose into a single stream; one male coupling to two female couplings.
significant events FRSC Fire Reporting Subcommittee Approved In the ICS209, observed fire behavior or significant incident events for the current reporting period.
significant fire event Fire Weather Subcommittee FWS Approved An event measured by the occurrence of fire(s) that requires mobilization of additional resources from outside the fire event area.
significant fire potential Fire Weather Subcommittee FWS Approved The likelihood a wildland fire event will require mobilization of additional resources from outside the area in which the fire situation originates.
significant weather trigger Fire Weather Subcommittee FWS Approved A weather phenomenon resulting in an environment that has a significant impact on fire spread, intensity, or occurrence. Example: strong wind, unstable air mass, etc.
Simms bucket National Interagency Aviation Committee NIAC Approved Self-leveling helibucket slung under a helicopter which can be filled by hovering over a water source.
simple hose lay Equipment Technology Committee ETC Approved A hose lay consisting of consecutively coupled lengths of hose without laterals. The lay is extended by inserting additional lengths of hose in the line between pumps and nozzle.
simulation Incident and Position Standards Committee IPSC Archived An activity that imitates something real, but it is not real itself and it can be altered by users for the specific purpose of providing an experiential learning environment. Examples: Sand Table Exercise or CBT/WBT Forest Service Wildland Fire Simulation Scenario Editor. 
simulation (event) National Coordination System Committee NCSC Approved An event dealing with simulation of various situations to provide experience or proficiency.
single arsonist Wildland Fire Investigation Subcommittee WFISC Approved An offender who intentionally sets one fire.
single door drop National Interagency Aviation Committee NIAC Approved Technique whereby fire retardant is released from only one compartment of an airtanker.
Single Resource National Incident Management System Integration Committee NIMSIC Approved An individual, a piece of equipment and its personnel complement, or a crew/team of individuals with an identified work supervisor that can be used on an incident.
single shift Incident Business Committee IBC Approved Equipment is staffed with 1 operator or crew. A normal shift could be up to 16 hours long and may cross calendar days.
single stage pump Equipment Technology Committee ETC Approved Centrifugal pump with a single impeller.
site preparation Fire Use Subcommittee FUSC Approved Removal or killing of unwanted vegetation, residue, etc. by use of fire, herbicides, or mechanical treatment in preparation for reforestation and future management.
site preparation burning Fire Use Subcommittee FUSC Approved Fire ignited to expose adequate mineral soil and control competing vegetation until seedlings of the desired species become established.
situation analysis IFPC Interagency Fire Planning Committee Approved Analysis of factors which influence suppression of an escaped fire from which a plan of attack will be developed; includes development of alternative strategies of fire suppression and net effect of each.
Situation Awareness (SA) Leadership Committee LC Approved An on-going process of gathering information by observation and by communication with others. This information is integrated to create an individual's perception of a given situation.
Situation Unit National Incident Management System Integration Committee NIMSIC Approved Situation Unit staff collect, process, and organize situation information, prepare situation summaries, produce maps, and develop projections and forecasts related to the incident. They gather and disseminate information for incident and agency decision processe.
Situational Awareness (SA) Leadership Committee LC Approved An on-going process of gathering information by observation and by communication with others. This information is integrated to create an individual's perception of a given situation.
Six Minutes for Safety (6MFS) Risk Management Committee RMC Approved A daily safety briefing for wildland fire that focuses on high risk events found within a firefighter's scope of work that are performed on an infrequent basis.
size class Approved Identifies the fire size based on number of acres within the final fire perimeter
size class of fire IOSC Incident Operations Subcommittee Approved As to size of wildfire: Class A - one-fourth acre or less; Class B - more than one-fourth acre, but less than 10 acres; Class C - 10 acres or more, but less than 100 acres; Class D - 100 acres or more, but less than 300 acres; Class E - 300 acres or more, but less than 1,000 acres; Class F - 1,000 acres or more, but less than 5,000 acres; Class G - 5,000 acres or more.
sizeup IOSC Incident Operations Subcommittee Approved The evaluation of the fire to determine a course of action for suppression.
skid hose load Equipment Technology Committee ETC Approved Load of hose specially arranged on top of a standard hose load to permit dropping the working line at the fire.
skid trail IOSC Incident Operations Subcommittee Approved Any road or trail formed by the process of skidding logs from stump to landing.
skidder unit Equipment Technology Committee ETC Approved A self-contained unit consisting of a water tank, fire pump, and hose specially designed to be carried on a logging skidder for use in forest fire suppression.
skimmer National Interagency Aviation Committee NIAC Approved Any aircraft equipped to pick up water while moving on or over water.
sky cover Fire Weather Subcommittee FWS Approved Amount of clouds and/or other obscuring phenomena that are detectable from the point of observation.
slash Fire Use Subcommittee FUSC Approved Debris resulting from such natural events as wind, fire, or snow breakage; or such human activities as road construction, logging, pruning, thinning, or brush cutting. It includes logs, chunks, bark, branches, stumps, and broken understory trees or brush.
slash disposal Fire Use Subcommittee FUSC Approved Treatment of slash to reduce fire hazard or for other purposes. Preferred to "brush disposal."
sling National Interagency Aviation Committee NIAC Approved A net attached by a lanyard to a helicopter cargo hook and used to haul supplies.
sling load Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved Any cargo carried beneath a helicopter and attached by a lead line and swivel.
sling psychrometer Equipment Technology Committee ETC, National Interagency Aviation Committee NIAC Approved A hand operated instrument for obtaining wet and dry bulb temperature readings and, subsequently, relative humidity.
slip-on tanker Equipment Technology Committee ETC Approved A tank, a live hose reel or tray, an auxiliary pump, and an engine combined into a single one-piece assembly which can be slipped onto a truck bed or trailer.
slip-on unit MFES Mobile Fire Equipment Subcommittee Approved A self-contained unit including an auxiliary engine driven pump, piping, a tank, and hose storage that is designed to be placed on a truck chassis, utility bed, flat bed, or trailer. Such units can typically be attached and removed from the vehicle with a minimum amount of time and effort.
slope class FDSC Fire Danger Subcommittee Approved One of five categories used to describe the topography of a fire danger rating area.
slope percent FDSC Fire Danger Subcommittee Approved The ratio between the amount of vertical rise of a slope and horizontal distance as expressed in a percent. One hundred feet of rise to 100 feet of horizontal distance equals 100 percent.
slope percentage (Point of Origin) (POO) Geospatial Subcommittee GSC Approved The ratio between the amount of vertical rise and horizontal distance of the terrain as expressed in a percent that represents the typical slope in the immediate vicinity of the point of origin of a fire. Point of origin is the location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred.
slope winds Fire Weather Subcommittee FWS Approved Small scale convective winds that occur due to local heating and cooling of a natural incline of the ground.
slopover IOSC Incident Operations Subcommittee Approved A fire edge that crosses a control line or natural barrier intended to confine the fire.
slug flow Equipment Technology Committee ETC Approved The discharge of distinct pockets of water and air due to the insufficient mixing of foam concentrate, water, and air in a compressed air foam system.
small aircraft National Interagency Aviation Committee NIAC Approved An aircraft of 12,500 pounds (5,669 kg) or less, maximum certificated takeoff weight.
smog Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved Generally considered only photochemical air pollution. Originally meant a combination of smoke and fog.
smoke Wildland Fire Investigation Subcommittee WFISC Approved Small particles of carbon, tarry and water vapor resulting from the incomplete combustion of carbonaceous materials such as wood, coal or oil.
smoke concentration Fire Use Subcommittee FUSC Approved The amount of combustion products found in a specified volume of air, commonly expressed as micrograms of emission per cubic meter of air.
smoke intrusion Fire Use Subcommittee FUSC Approved Smoke from prescribed fire entering a designated area at unacceptable levels.
smoke management Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved The policies and practices implemented by air and natural resource managers directed at minimizing the amount of smoke entering populated areas or impacting sensitive sites, avoiding significant deterioration of air quality and violations of National Ambient Air Quality Standards, and mitigating human-caused visibility impacts in Class I areas. 
smoke pall Fire Behavior Subcommittee FBSC Approved Extensive, thick blanket of smoke spreading more or less horizontally from a fire.
smoke plume Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved The gases, smoke, and debris that rise slowly from a fire while being carried along the ground because the buoyant forces are exceeded by those of the ambient surface wind.
Smoke Sensitive Area (SSA) Fire Use Subcommittee FUSC Approved Area in which smoke from outside sources is intolerable, for reasons such as heavy population, existing air pollution, or intensive recreation or tourist use.
smoke target Fire Use Subcommittee FUSC Approved An area that may be adversely affected by smoke from a prescribed burn.
smoke vent height Fire Weather Subcommittee FWS Approved Level, in the vicinity of the fire, at which the smoke ceases to rise and moves horizontally with the wind at that level.
Smoke-Induced Fog (SIF) Smoke Committee SmoC Approved A dense fog (water droplets suspended in the atmosphere) that forms away from a fire site when surface smoke comprised of increased fine particulates and water vapor, combines with ambient air that is already prone to natural fog formation.
Smokey Bear Communication, Education, and Prevention Committee CEPC Approved The symbol of the Cooperative Forest Fire Prevention Program since 1945. Smokey's image is protected by US Federal Law and is administered by the USDA Forest Service, the National Association of State Foresters and the Ad Council.
smoking Communication, Education, and Prevention Committee CEPC In Development Discarded or improperly managed cigarette butts or other smoking paraphanalia that leads to a wildfire ignition.
smoking (as a fire cause) Wildland Fire Investigation Subcommittee WFISC Approved Wildfires caused by smokers from matches, lighters, tobacco, or other smoking material.
smoldering combustion Fire Use Subcommittee FUSC Approved Combined processes of dehydration, pyrolysis, solid oxidation, and scattered flaming combustion and glowing combustion, which occur after the flaming combustion phase of a fire; often characterized by large amounts of smoke consisting mainly of tars.
smoldering combustion phase Fire Use Subcommittee FUSC Approved Phase of combustion immediately following flaming combustion. Emissions are at twice that of the flaming combustion phase.
snag Hazard Tree and Felling Subcommittee HTTFS Approved A standing dead tree or part of a dead tree from which at least the leaves and smaller branches have fallen. Often known as a stub, if less than 20 feet tall.
snorkel tank National Interagency Aviation Committee NIAC Approved A fixed tank attached to the belly of the helicopter that has a pump-driven snorkel attached. The helicopter hovers over the water source with the end of the snorkel immersed, the pump then fills the tank.
soft suction Equipment Technology Committee ETC Approved Commonly accepted term for short length of large diameter soft hose used to connect a structural or wildland engine with a hydrant. No vacuum is involved because the hose is useful only when the engine receives water at a rate of flow in excess of the demand of the pump. 
solar radiation FDSC Fire Danger Subcommittee Approved The amount of sunlight exposed to the fuels.
solar utility system Communication, Education, and Prevention Committee CEPC In Development Photovolaticis (PV) or concentrating solar power (CSP) systems
soot Fire Weather Subcommittee FWS Approved Carbon dust formed by incomplete combustion.
sooting fire pattern indicator Wildland Fire Investigation Subcommittee WFISC Approved Objects displaying more soot deposits on the exposed surface of the object than on the protected surface of the object indicating the direction of fire progression at that location. One of the 11 NWCG categories of fire pattern indicators.
sortie National Interagency Aviation Committee NIAC Approved Single round trip made by an airtanker from a tanker base to a fire and return.
sound warbler National Interagency Aviation Committee NIAC Approved A signaling device mounted on retardant aircraft which generates a tremulous siren sound to warn firefighters on the ground that a plane is approaching to drop retardant.
sounding (upper air sounding) Fire Weather Subcommittee FWS Approved A sampling of upper air conditions made by means of instruments and a small radio transmitter on a free balloon. Automatic radio signals originated by action of weather instruments are sent to a ground receiver. These signals are interpreted for use in analyzing and predicting upper air conditions over a wide area of the earth. Weather elements determined at a number of altitude points as the balloon rises are temperature, atmospheric moisture, pressure, wind direction and speed. Similar soundings may be made using fixed balloons or tethersondes.
source Fire Weather Subcommittee FWS Approved A point, line, or area, at which mass or energy is added to a system, either instantaneously or continuously. Examples of sources in the context of air pollution are as follows: a smoke stack is a point source; a freeway is a line source; field or slash burning are area sources.
source (documentation) Approved Supporting documentation on process used to map or collect data.
source agency Approved Land management agency with responsibility for creating and administering the data.
source depth (water) Approved Depth in feet of the water source.
source gallon capacity (water source) Approved Capacity in gallons of the water source.
source hyperlink (mapping) A link to documentation about the mapping effort
spalling Wildland Fire Investigation Subcommittee WFISC Approved Chipping or pitting of concrete, masonry, or stone surfaces.
span National Interagency Aviation Committee NIAC Approved Distance equal to the wingspread of the airtanker being used; used for corrections right or left of the flight path.
span of control National Incident Management System Integration Committee NIMSIC Approved The number of subordinates for which a supervisor is responsible, usually expressed as the ratio of supervisors to individuals. The optimum ratio is five-to-one.
spanner Equipment Technology Committee ETC Approved Metal wrench used to tighten and free hose connections.
spark arrester Equipment Technology Committee ETC Approved A device installed in a chimney, flue, or exhaust pipe to stop the emission of sparks and burning fragments.
Special Interest Group (SIG) FDSC Fire Danger Subcommittee Approved In WIMS, a group of weather stations.
special land designator FRSC Fire Reporting Subcommittee Approved Officially designated special land types within the fire perimeter.
Special Visual Flight Rules (VFR) National Interagency Aviation Committee NIAC Approved Aircraft operating in accordance with clearances within control zones in weather conditions less than the basic Visual Flight Rules weather minima.
specific heat Fire Weather Subcommittee FWS Approved The heat required to raise a unit mass of a substance one degree kelvin. It is the heat capacity of a system per unit mass; i.e., the ratio of the heat absorbed (or released) to the corresponding temperature rise (or fall).
Specific Origin Area (SOA) Wildland Fire Investigation Subcommittee WFISC Approved The smaller area within the general origin area where the fire's direction of spread was first influenced by fuel, weather, and/or topography.
speed of attack IOSC Incident Operations Subcommittee Archived Elapsed time from origin of fire to arrival of the first suppression force.
spike-out IOSC Incident Operations Subcommittee Approved Standby crew in an area of expected high fire occurrence, generally on a day of critical fire weather.
split drop Equipment Technology Committee ETC Approved Retardant drop made from one compartment at a time from an airtanker with a multi-compartment tank.
split flow Fire Weather Subcommittee FWS Approved A divergent wind field. Storms moving into a split field tend to lose strength. Winds are generally light in such a flow field.
spontaneous combustion Communication, Education, and Prevention Committee CEPC In Development An ignition that occurs when materials geneate heat internally, often due to chemical reactions, leading to a fire without an external spark or flame.
spontaneous combustion Wildland Fire Investigation Subcommittee WFISC Approved Combustion of a thermally isolated material initiated by an internal chemical or biological reaction producing enough heat to cause ignition.
spot burning Fire Use Subcommittee FUSC Approved A modified form of broadcast slash burning in which the greater accumulations of slash are fired and the fire is confined to these spots.
spot change Incident Business Committee IBC Approved The second continuous day of an incident, a regular government employee's normal daily tour of duty is "spot changed" to where the first 8, 9, or 10 hours worked are base hours.
spot fire Fire Behavior Subcommittee FBSC Approved Fire ignited outside the perimeter of the main fire by a firebrand.
spot fire technique Fire Use Subcommittee FUSC Approved A method of lighting prescribed fires where ignition points are set individually at a predetermined spacing and with predetermined timing throughout the area to be burned.
spot weather forecast Fire Weather Subcommittee FWS Approved A special forecast issued to fit the time, topography, and weather of a specific incident. These forecasts are issued upon request of the user agency and are more detailed, timely, and specific than zone forecasts. Usually, on-site weather observations or a close, representative observation is required for a forecast to be issued. 
spotter Interagency Helicopter Operations Subcommittee IHOPS Approved In smokejumping, rappelling, and paracargo operations, the individual responsible for selecting drop target and supervising all aspects of dropping smokejumpers, rappellers, or cargo.
spotting Fire Behavior Subcommittee FBSC Approved Behavior of a fire producing sparks or embers that are carried by the wind and which start new fires beyond the zone of direct ignition by the main fire.
spray IOSC Incident Operations Subcommittee Approved Water applied through an orifice in finely divided particles to absorb heat and smother fire, to protect exposures from radiated heat, and to carry water toward otherwise inaccessible fire.
spread component FDSC Fire Danger Subcommittee Approved A rating of the forward rate of spread of the head of a fire.
spread index FDSC Fire Danger Subcommittee Approved A number used to indicate relative (not actual) rate of spread.
spread index meter FDSC Fire Danger Subcommittee Approved Device for combining measured ratings of various fire danger factors into numerical classes or rates of spread.
spur ridge Fire Environment Committee FENC Approved A small ridge which extends finger-like from a main ridge.
squall Fire Weather Subcommittee FWS Approved Sudden increase in wind speed to at least 17 mph (15 knots) that is sustained for at least 1 minute but not more than 5 minutes.
squall line Fire Weather Subcommittee FWS Approved Any nonfrontal line or narrow band of active thunderstorms extending across the horizon. It is of importance to fire behavior due to accompanying strong gusty winds and the possibility of such a line passing between regular weather observation stations without being reported.
stable atmosphere Fire Weather Subcommittee FWS Approved Condition of the atmosphere in which the temperature decrease with increasing altitude is less than the dry adiabatic lapse rate. In this condition, the atmosphere tends to suppress large-scale vertical motion.
stable layer of air Fire Weather Subcommittee FWS Approved A layer of air having a temperature change (lapse rate) of less than dry adiabatic (approximately -5.4 degrees F per 1,000 feet) thereby retarding either upward or downward mixing of smoke.
stack IASS Interagency Aerial Supervision Subcommittee Approved Aircraft orbiting the rendezvous area; usually refers to vertical deployment at 500-foot (150 m) altitudinal separation between aircraft.
staff ride Leadership Committee LC Approved A case study of a previous incident that is conducted on the actual physical site where the incident occurred. A staff ride is an experiential learning method that involves three distinct parts: a preliminary study, a site visit, and a post-visit integration session. 
staffing index FDSC Fire Danger Subcommittee Approved A NFDRS component, index or related indicator (ignition component, spread component, energy release component, burning index, Keetch-Byram drought index) whose outputs are correlated to the local fire problem, used to determine staffing levels.
staffing level FDSC Fire Danger Subcommittee Approved The basis for decision support for daily staffing of initial attack resources and other activities. A level of readiness and an indicator or daily preparedness.
Staging Area National Incident Management System Integration Committee NIMSIC Approved A temporary location for available resources in which personnel, supplies, and equipment await operational assignment.
stagnant conditions Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved Atmospheric conditions under which pollutants build up faster than the atmosphere can disperse them.
stand replacing fire Fire Use Subcommittee FUSC Approved Fire which kills all or most of the living overstory trees in a forest and initiates forest succession or regrowth. Also explicitly describes the nature of fire in grasslands and some shrublands.
stand-by crew IOSC Incident Operations Subcommittee Approved A group of trained firefighters stationed at a dispatch point for quick, rapid deployment.
standard coupling Equipment Technology Committee ETC Approved Fire hose coupling with American National Standard (NH) threads.
standard drying day FDSC Fire Danger Subcommittee Approved Day which produces the same net drying as experienced during a 24-hour period under laboratory conditions in which dry-bulb temperature is maintained at 80º F and relative humidity is maintained at and relative humidity is maintained at 20%.
Standard Hydrologic Exchange Format (SHEF) code FDSC Fire Danger Subcommittee Approved A two-character code to describe each measurement taken at a weather station.
Standard Operating Procedure (SOP) Leadership Committee LC Approved Specific instructions clearly spelling out what is expected of an individual every time they perform a given task. A standard operating procedure can be used as a performance standard for tasks that are routinely done in the operational environment.
Standard Operational Procedure (SOP) Leadership Committee LC Approved Specific instructions clearly spelling out what is expected of an individual every time they perform a given task. A standard operational procedure can be used as a performance standard for tasks that are routinely done in the operational environment.
state (initial attack frequency) Approved State in which initial attack frequency zone sits.
state (Point of Origin) (POO) FRSC Fire Reporting Subcommittee Approved The Country and State alpha code identifying the state or equivalent entity at point of origin.
state and landowner final fire acre quantity FRSC Fire Reporting Subcommittee Approved Number of acres measured by each Landowner Kind and Category within a State Code associated with the land within the final fire perimeter of a specific, individual incident. The area measured within the perimeter includes unburned and unburnable islands or portions of such.
state code Data Management Committee DMC Superceded A code for the identification of the states, the District of Columbia and the outlying areas of the United States, and associated areas.
state financial code Proposed New A state agency specific accounting identifier.
state forest IOSC Incident Operations Subcommittee Archived Forests owned and administered by a state, and not by a federal government.
state of weather Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved A code which expresses the amount of cloud cover, kind of precipitation, and/or restrictions to visibility being observed at the fire danger station at basic observation time.
state park IOSC Incident Operations Subcommittee Archived An area established by the government of a state primarily for public recreation or for the preservation of unique natural or historic resources, administrative details varying widely. NOTE: Such parks may also be established by lesser administrative units, e.g. counties, municipalities, and also by large private owners. 
static pressure Equipment Technology Committee ETC Approved Water pressure head available at a specific location when no water is being used so that no friction loss is being encountered. Static pressure is that pressure observed on the engine inlet gauge before any water is taken from the hydrant.
static water supply Equipment Technology Committee ETC Approved Supply of water at rest which does not provide a pressure head for fire suppression but which may be employed as a suction source for fire pumps (e.g., water in a reservoir, pond, or cistern).
station catalog FDSC Fire Danger Subcommittee Approved A WIMS file that contains all the information defined for a weather station.
station ID FDSC Fire Danger Subcommittee Approved A six-digit number assigned to a specific weather station by the servicing National Weather Service Fire Weather Office.
station pressure Fire Weather Subcommittee FWS Approved Pressure of the atmosphere at an assigned station location and elevation.
statistic Fire Weather Subcommittee FWS Approved The number that results from manipulating raw data according to a specified procedure; associated with samples.
statistical fire Wildland Fire Investigation Subcommittee WFISC Approved In general, an actionable fire, on which any fire agency reports and maintains specified information (e.g., cause, date and point of origin, size, fire damage).
statistics Fire Weather Subcommittee FWS Approved A branch of mathematics dealing with the collection, analysis, and interpretation of numerical data.
step test Risk Management Committee RMC Approved Five-minute test used to predict a person's ability to take in, transport, and use oxygen (aerobic capacity), the most important factor limiting the ability to perform arduous work.
storm center Fire Weather Subcommittee FWS Approved The central point or area of a weather system associated with increased winds, clouds or precipitation (or any combination thereof).
straight stream Equipment Technology Committee ETC Approved Water or fire retardant projected directly from the nozzle (as contrasted with a fog or spray cone), provided by a solid stream orifice or by adjusting a fog jet into a straight stream pattern.
straight stream nozzle Equipment Technology Committee ETC Approved A hose tip spout designed to provide the maximum reach of water without feathering.
strainer Equipment Technology Committee ETC Approved A wire or metal guard used to keep debris from clogging pipe or other openings made for removing water; used in pumps and on suction hose to keep foreign material from clogging or damaging pumps.
strategic objective FMB Fire Management Board Approved A broad statement, specified in a land/resource management or fire management plan that identifies change in water, soil, air, or vegetation from the present to proposed conditions, or describes an existing resource condition that should be maintained. Strategic objectives deal with large areas over long time periods and project intended outcomes of management activities that contribute to the maintenance or achievement of desired conditions. 
strategy wfnwcgorg:ICSC Approved The general plan or direction selected to accomplish incident objectives.
strength of attack IOSC Incident Operations Subcommittee Archived Number of resources used to attack a fire.
strength of force IOSC Incident Operations Subcommittee Archived Total firefighting resources available, during a specified period, to conduct and support firefighting operations.
Strike Team National Incident Management System Integration Committee NIMSIC Approved A set number of resources of the same kind and type that have an established minimum number of personnel, common communications, and a leader.
stringer Fire Environment Committee FENC Approved A narrow finger or band of fuel that connects two or more patches or areas of wildland fuel.
strip burning (firing) Fire Use Subcommittee FUSC Approved Burning by means of strip firing.
strip burning (hazard reduction) Fire Use Subcommittee FUSC Approved In hazard reduction, burning narrow strips of fuel and leaving the rest of the area untreated by fire.
strip firing Fire Use Subcommittee FUSC Approved Setting fire to more than one strip of fuel and providing for the strips to burn together. Frequently done in burning out against a wind where inner strips are fired first to create drafts which pull flames and sparks away from the control line.
strip-head fire Fire Use Subcommittee FUSC Approved A series of lines of fire ignited near and up wind (or downslope) of a firebreak or backing fire so they burn with the wind (or upslope) toward the firebreak or backing fire.
structural fire protection IOSC Incident Operations Subcommittee Approved The protection of homes or other structures from an active wildland fire.
structure Communication, Education, and Prevention Committee CEPC In Development When flames from a burning building or other structure extend beyond the immediate area and ignite surrounding vegetation.
structure (constructive) Wildland Fire Investigation Subcommittee WFISC Approved A constructed object, usually a free-standing building above ground.
structure (vegetative) Fire Use Subcommittee FUSC Approved The arrangement of vegetation in terms of density, basal area, cover, and vertical arrangement.
structure accident (event) National Coordination System Committee NCSC Approved An event dealing with a major accident or mishap such as collapse of a building or other man-made structure.
structure fire Wildland Fire Investigation Subcommittee WFISC Approved Fire originating in and burning any part or all of any building, shelter, or other structure.
structure fire (event) National Coordination System Committee NCSC Approved An event dealing with a fire originating in and burning any part or an entire building, shelter, or other structure.
Structure Ignition Zone (SIZ) WMSC WUI Mitigation Subcommittee Approved The characteristics of a structure and its immediate surroundings within 100 feet; the SIZ may be extended (e.g., to 150 or 200 feet) in areas of steep terrain or dense, highly flammable vegetation. The SIZ is the key determinant for structure ignition potential during wildfire.
structure protection plan IOSC Incident Operations Subcommittee Approved A plan developed by the Structure Protection Specialist that provides operational guidelines to suppression resources responsible for providing wildland fire structure protection.
subsidence Fire Weather Subcommittee FWS Approved Downward or sinking motion of air in the atmosphere. Subsiding air warms due to compression. Increasing temperature and decreasing humidities are present in subsiding air. Subsidence results in a stable atmosphere inhibiting dispersion. Subsidence is generally associated with high atmospheric pressure. 
subsidence inversion Fire Weather Subcommittee FWS Approved An inversion caused by subsiding air, often resulting in decreased atmospheric mixing conditions.
succession Fire Use Subcommittee FUSC Approved The process of vegetational development whereby an area becomes successively occupied by different plant communities of higher ecological order.
suction lift Equipment Technology Committee ETC Approved In fire service, the number of feet (meters) of vertical lift from the surface of the water to the center of the pump impeller. In testing, e.g., fire department pumpers are required to discharge their rated capacity at 150 pounds (1034 kPa) net pump pressure at a 10-foot (3 meter) lift. The suction gauge would indicate the vertical suction lift in inches of mercury when the pump was primed with no appreciable water flowing. 
sunny Fire Weather Subcommittee FWS, FDSC Fire Danger Subcommittee Approved The adjective classification of the sky when 5/10 or less of the sky is obscured by clouds.
sunset and sunrise Fire Weather Subcommittee FWS Approved The mean solar times of sunset and sunrise as published in the Nautical Almanac, converted to local standard time for the locality concerned.
superficial burn Risk Management Committee RMC Approved A minor thermal burn involving the outer layer of skin, i.e. "a sunburn". It is characterized by reddening of the skin and perhaps some swelling without blisters.
superfog Smoke Committee SmoC Approved An extremely dense surface fog (water droplets suspended in the atmosphere) at the site of combustion that reduces visibility to less than three meters (ten feet).
supervisor National Incident Management System Integration Committee NIMSIC Approved The ICS title for an individual responsible for a division or group.
supplemental fire department resources Incident Business Committee IBC Approved Overhead tied to a local fire department, generally by agreement, who are mobilized primarily for response to incidents or wildland fires outside their district or mutual aid zone. Supplemental fire department resources are not a permanent part of the local fire organization and are not required to attend scheduled training, meetings, etc. of the department staff. 
supplies Equipment Technology Committee ETC Approved Minor items of equipment and all expendable items assigned to an incident.
Supply Unit National Incident Management System Integration Committee NIMSIC Approved Supply Unit staff order, receive, process, store, inventory, and distribute all incident-related supplies. The Supply Unit staff are responsible for all off-incident ordering.
Support Branch National Incident Management System Integration Committee NIMSIC Approved A branch within the logistics section responsible for providing personnel, equipment and supplies to support incident operations. Includes the supply, facilities and ground support units.
support costs Incident Business Committee IBC Approved On-incident costs and off-incident costs. On-incident costs include caterer, shower units, mobile commissary, cache supplies, and materials, etc. Off-incident costs include expanded dispatch, buying teams, administrative payment teams, cache personnel, area command, transportation to/from incident, etc. 
support resources wfnwcgorg:ICSC Approved Non-tactical resources under the supervision of the logistics, planning, finance/administration sections or the command staff.
supporting agency wfnwcgorg:ICSC Approved An agency providing suppression or other support and resource assistance to a protecting agency.
supporting technologies National Coordination System Committee NCSC Approved Any technology which may be used to support NIIMS. Examples of these technologies include GIS mapping, infrared technology, NFDRS, communications, dispatch coordination, and national cache system.
suppress a fire IOSC Incident Operations Subcommittee Approved see: Suppression
suppressant Equipment Technology Committee ETC Approved An agent that extinguishes the flaming and glowing phases of combustion by direct application to the burning fuel.
suppression FMB Fire Management Board Approved All the work to extinguish or limit wildland fire spread.
suppression crew IOSC Incident Operations Subcommittee Approved Two or more firefighters stationed at a strategic location for initial action on fires. Duties are essentially the same as those of individual firefighters.
suppression firing IOSC Incident Operations Subcommittee Archived Intentional application of fire to speed up or strengthen fire suppression action on wildfires. Types of suppression firing include burning out, counter firing, and strip burning.
surface area-to-volume ratio Fire Weather Subcommittee FWS Approved The ratio between the surface area of an object, such as a fuel particle, to its volume. The smaller the particle, the more quickly it can become wet, dry out, or become heated to combustion temperature during a fire.
surface fire Fire Use Subcommittee FUSC Approved Fire that burns loose debris on the surface, which includes dead branches, leaves, and low vegetation.
surface fuel Fire Use Subcommittee FUSC Approved Fuels lying on or near the surface of the ground, consisting of leaf and needle litter, dead branch material, downed logs, bark, tree cones, and low stature living plants.
surface high Fire Weather Subcommittee FWS Approved An area on the earth's surface where atmospheric pressure is at a relative maximum. Winds blow clockwise around highs in the Northern Hemisphere but, due to friction with the earth's face, tend to cross constant pressure lines away from the high center. Air is usually subsiding above a surface high. This causes warming due to air compression. This results in stable atmospheric conditions and light surface winds. 
surface low Fire Weather Subcommittee FWS Approved An area on the earth's surface where atmospheric pressure is at a relative minimum. Winds blow counter-clockwise around lows in the Northern Hemisphere but, due to friction with the earth's surface, tend to cross constant pressure lines toward the low center. Upon converging into the low's center, air currents are forced to rise. As air rises it cools due to expansion. Cooling reduces its capacity to hold moisture; so cloudiness and precipitation are common in lows. If a low center intensifies sufficiently it will take on the characteristics of a storm center with precipitation and strong winds.
surface tension Equipment Technology Committee ETC Approved The elastic-like force at the surface of a liquid, tending to minimize the surface area and causing drops to form. Expressed as Newtons per meter or dynes per centimeter (1 Newton/m=1,000 dynes/cm).
surface wind Fire Weather Subcommittee FWS Approved Wind measured at a surface observing station, customarily at some distance (usually 20 feet) above the average vegetative surface to minimize the distorting effects of local obstacles and terrain.
surfactant Equipment Technology Committee ETC Approved A surface active agent; any wetting agent. A formulation which, when added to water in proper amounts, will materially reduce the surface tension of the water and increase penetration and spreading abilities of the water.
surge Equipment Technology Committee ETC Approved Rapid increase in water flow which may result in a corresponding pressure rise.
surplus property Equipment Technology Committee ETC Approved Any excess personal property not required for the needs and the discharge of the responsibilities of all federal agencies as determined by the General Services Administration (GSA).
survival zone Risk Management Committee RMC Approved A natural or cleared area of sufficient size and location to protect fire personnel from known hazards while inside a fire shelter. Examples include rock slides, road beds, clearings, knobs, wide ridges, benches, dozer lines, wet areas, cleared areas in light fuels, and previously burned areas. These are all areas where you expect no flame contact or prolonged heat and smoke. 
suspended fuel Wildland Fire Investigation Subcommittee WFISC Approved A wildland fuel that is suspended off the ground in such a way that fire may burn both over and under it.
sustainability (water source) Approved A measure of the refresh rate of the water source.
sustained attack IOSC Incident Operations Subcommittee Archived Continuing fire suppression action until fire is under control.
swamper (dozer) Hazard Tree and Felling Subcommittee HTTFS Approved A worker on a dozer crew who pulls winch line, helps maintain equipment, etc., to speed suppression work on a fire.
swamper (faller/sawyer) Hazard Tree and Felling Subcommittee HTTFS Approved A worker who assists fallers and/or sawyers by clearing away brush, limbs and small trees. Carries fuel, oil and tools and watches for dangerous situations.
swampout Hazard Tree and Felling Subcommittee HTTFS Approved Act of clearing brush and other material from around the base of trees and where trees are to be bucked, prior to falling or bucking, as protection against saw kickback and to provide safe footing.
swivel Equipment Technology Committee ETC Approved An accessory used between the helicopter cargo hook and sling load to allow free turning of the load.
synoptic Fire Weather Subcommittee FWS Approved Literally, at one time. Thus, in meteorological usage, the weather conditions over a large area at a given point in time.
synoptic chart Fire Weather Subcommittee FWS Approved In meteorology, any chart or map on which data and analyses are presented that describe the state of the atmosphere over a large area at a given moment in time.
systematic methodology Wildland Fire Investigation Subcommittee WFISC Approved The systematic application of methods, procedures, and techniques common to the field of wildand fire investigation as regularly applied to solve the problems of the investigation within each specifc scene's conditions and needs.
T-card National Incident Management System Integration Committee NIMSIC Approved Cards filled out with essential tracking information for each resource they represent. The cards are color-coded to represent different types of resources.
Tactical Decision Game (TDGS) Leadership Committee LC Approved A simple role-play simulation technique that challenges participants to make decisions and communicate those decisions to others. A tactical decision game is an experiential learning method that is tactical in nature and has time and information constraints to put participants under some level of stress.
tactical direction IOSC Incident Operations Subcommittee Approved Direction given by the operations section chief which includes the tactics appropriate for the selected strategy, the selection and assignment of resources, tactics implementation, and performance monitoring for each operational period.
tactics IOSC Incident Operations Subcommittee, wfnwcgorg:ICSC Approved Deploying and directing resources on an incident to accomplish the objectives designated by strategy.
tag-on SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved Connecting a (airtanker) drop to the forward part of a previous drop.
tail number National Coordination System Committee NCSC Approved The numerical identification of an aircraft, also known as the registration number for an aircraft, as displayed on the aircraft’s tail section.
tail rotor National Interagency Aviation Committee NIAC Approved A small rotor, mounted on the tail of a conventional helicopter, which counteracts torque of the main rotor and provides a measure of directional control.
tailboard IOSC Incident Operations Subcommittee Archived Back step of a wildland or structural fire engine.
tailgate safety session Risk Management Committee RMC Approved Brief meetings held at the beginning, during, or end of an operational period to discuss new work assignments, new work methods, changes in plans, use of tools and equipment, and recognition and protection against work hazards that may be encountered.
tandem IOSC Incident Operations Subcommittee Approved Two or more units of any one type working one in front of the other to accomplish a specific fire suppression job; the term can be used in connection with crews of firefighters, power pumps, bulldozers, etc.
tank and gating system Equipment Technology Committee ETC Approved Tanks, doors, and release mechanism installed in aircraft for cascading fire retardants.
tank trailer Equipment Technology Committee ETC Approved Specialized trailer on which is mounted a tank, fire pump, hose, and ancillary equipment.
target IASS Interagency Aerial Supervision Subcommittee Approved Specific portion of the fire on which fire retardant or water is to be dropped by airtankers or helitankers.
target hazard Wildland Fire Investigation Subcommittee WFISC Approved Facilities in which there is great likelihood of loss of life or property.
task Leadership Committee LC Approved A specific description of a unit of work activity that is a logical and necessary action in the performance of a behavior; how the behavior is demonstrated or performed in a particular context.   From PMS 310-1  
Task Force National Incident Management System Integration Committee NIMSIC Approved Any combination of single resources assembled for a particular tactical need, with common communications and a leader. A task force may be pre-established and sent to an incident, or formed at an incident.
temperature coefficient Wildland Fire Investigation Subcommittee WFISC Approved The relative change of some measurable quantity with change of temperature, like burning time per unit length, mostly expressed as mean change per degree in percentage of mean temperature within a certain range.
temporary IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: Employing office is a government entity Term of appointment is not to exceed one year Employee receives compensation for work
Ten-hour Timelag Fuel Moisture (10-h TL FM) Fire Behavior Subcommittee FBSC, FDSC Fire Danger Subcommittee Approved The moisture content of the l0-hour timelag roundwood fuels.
ten-hour timelag fuels Fire Behavior Subcommittee FBSC, FDSC Fire Danger Subcommittee Approved Dead fuels consisting of roundwood 1/4 to l-inch (0.6 to 2.5 cm) in diameter and, very roughly, the layer of litter extending from immediately below the surface to 3/4 inch (1.9 cm) below the surface.
tender type (water source) Approved Largest tender type that can use the water source.
tentative release Proposed New A resource may be tentatively released from At Incident so that a dispatcher can have a view of where resources are and their availability to be assigned to an incident.
Terra Torch ® Equipment Technology Committee ETC Approved Device for throwing a stream of flaming liquid, used to facilitate rapid ignition during burn out operations on a wildfire or during a prescribed fire operation.
terrorism National Incident Management System Integration Committee NIMSIC Archived Any premeditated, unlawful act dangerous to human life or public welfare that is intended to intimidate or coerce civilian populations or governments.
test fire Fire Use Subcommittee FUSC Approved A prescribed fire set to evaluate such things as fire behavior, fire effects, detection performance, or control measures.
thermal belt Fire Weather Subcommittee FWS Approved An area of mountainous slope (characteristically the middle third), where the top of the radiation inversion intersects the slope. It typically experiences the least variation in diurnal temperatures and has the highest average temperatures and, thus, the lowest relative humidity. Its presence is most evident during clear weather with light wind. 
thermal imagery Fire Weather Subcommittee FWS Approved The display or printout of an infrared scanner operating over a fire.
thin layer Fire Weather Subcommittee FWS Approved Layer of clouds whose ratio of dense sky cover to total sky cover is 1/2 or less.
thin sky cover Fire Weather Subcommittee FWS Approved Sky cover through which higher clouds or the sky can be detected.
third-degree burn Risk Management Committee RMC Approved A flesh burn in which charring occurs.
third-party case Incident Business Committee IBC Approved An injury or illness/disease caused by a person or object under circumstances that indicate there may be a legal liability on a party other than the federal or state government.
threat IFPC Interagency Fire Planning Committee Approved An incident likely to cause damage or danger to protected lands.
threat fire IOSC Incident Operations Subcommittee Approved Any uncontrolled fire near to or heading toward an area under organized fire protection.
throw out IOSC Incident Operations Subcommittee Archived Soil pushed over the edge of a fireline by a tractor plow or dozer.
thunderstorm Fire Weather Subcommittee FWS Approved Localized storm characterized by one or more electrical discharge(s).
thunderstorm/tornado/high winds (event) National Coordination System Committee NCSC Approved An event dealing with response to a severe storm such as thunderstorms, tornado, or high winds.
tie-in IOSC Incident Operations Subcommittee Approved Act of connecting a control line to another fireline or an intended firebreak.
time delay device Wildland Fire Investigation Subcommittee WFISC Approved A device employed to allow a firesetter the opportunity to leave the scene prior to the ignition of the fire.
time in service National Interagency Aviation Committee NIAC Approved With respect to maintenance time records, the time from the moment an aircraft leaves the surface of the earth until it touches at the next point of landing.
time point Data Management Committee DMC Approved A point in time during a 24-hour Coordinated Universal Time (UTC) day.
time recording Incident Business Committee IBC Approved Recording all time presented by others. Personnel time recorders record time from the Crew Time Report, SF-261, to the Incident Time Report, OF-288. Equipment time recorders record time from the Emergency Equipment Shift Ticket, OF-297, to the Emergency Equipment Use Invoice, OF-286.
Time Unit Incident Business Committee IBC Approved Functional unit within the Finance/Administration Section responsible for recording personnel time and managing the commissary.
time-temperature curve Fire Weather Subcommittee FWS Approved Graph showing the increase in temperature at a specified point in a fire as a function of time, beginning with ignition and ending with burnout.
timekeeping Incident Business Committee IBC Approved Tracking on-shift time of incident resources. Timekeeping is accomplished on the Crew Time Report, SF-261, or the Emergency Equipment Shift Ticket, OF-297.
Timelag (TL) FDSC Fire Danger Subcommittee Approved Time needed under specified conditions for a fuel particle to lose about 63 percent of the difference between its initial moisture content and its equilibrium moisture content. If conditions remain unchanged, a fuel will reach 95 percent of its equilibrium moisture content after 4 timelag periods. 
tinder Fire Use Subcommittee FUSC Approved Burnable organic material (duff, peat, rotten wood, etc.) with a high surface to volume ratio.
tips Equipment Technology Committee ETC Approved Nozzle tips used to change orifice size of a hose stream.
topographic map Incident and Position Standards Committee IPSC Approved A map that shows the positions of features, and also represents their vertical position in a measurable form.
torch (envelopment) Equipment Technology Committee ETC Approved Ignition and subsequent envelopment in flames, usually from bottom to top, of a tree or small group of trees.
torch (professional) Equipment Technology Committee ETC Approved A professional firesetter-for-hire.
torch (set fire) Equipment Technology Committee ETC Approved To set fire to property deliberately and maliciously.
torching Fire Behavior Subcommittee FBSC Approved The burning of the foliage of a single tree or a small group of trees, from the bottom up.
total fuel Fire Use Subcommittee FUSC Approved All plant material both living and dead that can burn in a worst case situation.
total mobility IOSC Incident Operations Subcommittee Approved The capability to move, position, and utilize established forces to meet existing and anticipated fire protection needs nationwide.
total risk FDSC Fire Danger Subcommittee Approved Sum of lightning and human-caused risk values.
Total Suspended Particulate Matter (TSP) Fire Use Subcommittee FUSC Approved Particles emitted from a pollution source regardless of size. Federal and state ambient and emission standards exist for TSP.
touchdown pad Interagency Helicopter Operations Subcommittee IHOPS Approved That portion of a heliport or helispot where the helicopter lands.
tour-of-duty Incident Business Committee IBC Approved The hours of a day (a daily tour-of-duty) and the days of an administrative workweek (a weekly tour-of-duty) that constitutes an employee's regularly scheduled administrative workweek.
township Incident and Position Standards Committee IPSC Approved An area of land divided by township lines and range lines which is approximately 36 miles square. Each township is divided into 36 parts, each approximately one mile square, called sections. Township lines, which are 6 miles apart, run east and west parallel to the Base Line (and also parallel to lines of latitude).
toxic Risk Management Committee RMC Approved Relating to a harmful effect by a poisonous substance on the human body by physical contact, ingestion, or inhalation.
toxic substance Risk Management Committee RMC Approved A chemical or mixture that may present an unreasonable risk of injury to health or the environment.
track replacement Communication, Education, and Prevention Committee CEPC In Development Replacement of railroad tracks or ties. Can be done with hand crews or a track renewal train.
tractor Equipment Technology Committee ETC Archived A rubber tired or tracked rider-controlled automotive vehicle, used in wildland fire management for pulling a disk or a plow to construct fireline by exposing mineral soil.
tractor plow Equipment Technology Committee ETC Approved A steel tracked vehicle with or without a front mounted blade equipped with a plow for exposing mineral soil. Sometimes a tractor plow with a front mounted blade is referred to as a dozer plow.
tractors/mowers/brush hogs Communication, Education, and Prevention Committee CEPC In Development
traffic pattern National Interagency Aviation Committee NIAC Approved Traffic flow that is prescribed for aircraft landing at, taxiing on, and taking off from, an airport. Usual components of a traffic pattern are upwind leg, crosswind leg, downwind leg, base leg, and final approach.
trail drop National Interagency Aviation Committee NIAC Approved An unbroken line of retardant used for constructing a retardant line.
trailer Communication, Education, and Prevention Committee CEPC In Development
trailer Wildland Fire Investigation Subcommittee WFISC Approved Combustible material, such as rolled rag, blankets and newspapers, or flammable liquid, used to spread fire from one area to others; usually used in conjunction with an incendiary device.
trainee Incident and Position Standards Committee IPSC Approved An individual who has met all required training and position experience for a specified position and is approved by their home unit's certifying official, to initiate a performance based training assignment in order to become qualified in the position.
trainer/coach Incident and Position Standards Committee IPSC Approved A position-qualified individual who provides instruction to a trainee in the classroom, on-the-job, or on an incident. While many of the requirements of the trainer/coach are similar to the evaluator, it is important that the roles of training and evaluation remain separate. 
training and proficiency (event) National Coordination System Committee NCSC Approved A scheduled activity that provides instruction to make attendees fit, qualified, or proficient in a particular area. This is a planned event.
training facility UIB Unit Identifier Board Approved An organizational unit limited to a training center that coordinates the delivery of national or geographic area/regional training.
transfer of command wfnwcgorg:ICSC Approved The ICS management process in which the on-scene incident commander at a specified time hands off command responsibilities to the incident commander that will be taking over incident command.
transition FDSC Fire Danger Subcommittee Approved In the 1978 version of NFDRS, the herbaceous stage when herbaceous fuel moisture is between 120% and 30%.
transition zone Wildland Fire Investigation Subcommittee WFISC Approved Area of change between advancing, lateral, and backing vectors.
translational lift National Interagency Aviation Committee NIAC Approved Lift that is gained when a helicopter translates from a hover into forward flight; additional lift increases with increasing airspeed and is derived by the rotor system moving into undisturbed air.
transport wind speed Fire Weather Subcommittee FWS Approved A measure of the average rate of the horizontal transport of air within the Mixing Layer. May also be the wind speed at the final height of plume rise. Generally refers to the rate at which emissions will be transported from one area to another.
transportation map Geospatial Subcommittee GSC Approved Base map of the planning unit showing all roads, trails, heliports, and airfields existing and programmed for construction.
travel time Incident Business Committee IBC Approved Compensable time en route to or from an emergency incident.
travel time map IOSC Incident Operations Subcommittee Archived Map showing the time required for the initial attack crew to reach various parts of a protection unit from specified positions.
treatment acres Communication, Education, and Prevention Committee CEPC Approved Acreage of treatment polygon as calculated with GIS
treatment category Communication, Education, and Prevention Committee CEPC Approved Describes major class of treatment.
treatment identifier Communication, Education, and Prevention Committee CEPC Approved Unique identifier for fuels treatment polygon(s).
treatment identifier database Communication, Education, and Prevention Committee CEPC Approved The database containing additional information related to the treatment identifier
treatment name Communication, Education, and Prevention Committee CEPC Approved The name of the fuels treatment
treatment status Communication, Education, and Prevention Committee CEPC Approved Status of the fuels treatment polygon(s).
treatment type Communication, Education, and Prevention Committee CEPC Approved Describes the kind of treatment work. Type is more specific than treatment category.
trench IOSC Incident Operations Subcommittee Approved A small ditch often constructed below a fire on sloping ground (undercut or underslung line) to catch rolling material.
triangulation
trough Fire Weather Subcommittee FWS Approved An elongated area of relatively low atmospheric pressure, usually extending from the center of a low pressure system.
truck trail IOSC Incident Operations Subcommittee Archived Substantial transportation route for fire suppression motor vehicles, built prior to a fire. Also known as a fire road.
true airspeed National Interagency Aviation Committee NIAC Approved Velocity of an aircraft in its flight path relative to the air through which it is moving.
true bearing IOSC Incident Operations Subcommittee Approved Bearing by true north rather than magnetic north.
true north
tsunami (event) National Coordination System Committee NCSC Approved An event dealing with response to a tsunami.
turbulence Fire Weather Subcommittee FWS Approved Irregular motion of the atmosphere usually produced when air flows over a comparatively uneven surface such as the surface of the earth; or when two currents of air flow past or over each other in different directions or at different speeds.
turn the corner IOSC Incident Operations Subcommittee Approved Contain a fire along a flank of the fire and begin containing it across the head. Refers to ground or air attack.
turnaround time SEATB Single Engine Airtanker Board, IAB Interagency Airtanker Board Approved Time used by an airtanker or helitanker to reload and return to the fire.
turnout coat Equipment Technology Committee ETC Approved A coat with a fire resistant outer shell and a thermal and moisture barrier liner. Used primarily by structure firefighters.
two-way radio National Coordination System Committee NCSC Approved Radio equipment with transmitters in mobile units on the same frequency as the base station, permitting conversation in two directions using the same frequency in turn.
type National Incident Management System Integration Committee NIMSIC Approved A NIMS resource classification that refers to capability of a specific kind of resource to which a metric is applied to designate it as a specific numbered class.
UAS model rockets & airplanes Communication, Education, and Prevention Committee CEPC In Development
Ultra High Frequency (UHF-FM) National Coordination System Committee NCSC Approved Radio frequencies from 300 Megahertz (MHz) to 3,000 MHz with a normal range of less than 50 miles. Radio frequency common to military aircraft and used in the logistics radio system. The most common frequencies used by fire and public safety are from 406 MHz to 512 MHz. 
unacceptable risk Risk Management Committee RMC Approved Level of risk as determined by the risk management process which cannot be mitigated to an acceptable safe level.
unauthorized passenger National Interagency Aviation Committee NIAC Approved All personnel who are not official or unofficial passengers are considered unauthorized passengers and are not authorized to be transported in any aircraft owned or operated by or on behalf of the government.
unavailable Proposed New The resource is not available to fill a resource order request.
unavailable (transferred) Proposed New The resource has been transferred to another dispatch, but the transfer has not been completed.
uncontrolled airport National Interagency Aviation Committee NIAC Approved Airport not having an approved agency with radio communications to direct aircraft take-offs and landings.
uncontrolled fire IOSC Incident Operations Subcommittee Approved Any fire which threatens to destroy life, property, or natural resources, and (a) is not burning within the confines of firebreaks, or (b) is burning with such intensity that it could not be readily extinguished with ordinary tools commonly available.
under investigation Communication, Education, and Prevention Committee CEPC In Development
underburn Fire Use Subcommittee FUSC Approved A fire that consume surface fuels but not the overstory canopy.
undercut line IOSC Incident Operations Subcommittee Approved A fireline below a fire on a slope. Should be trenched to catch rolling material.
understory burning Fire Use Subcommittee FUSC Approved Prescribed burning under a forest canopy.
undetermined Communication, Education, and Prevention Committee CEPC In Development Refers to wildfire incidents where an investigation did not identify a clear or definitive cause of origin.
unified area command wfnwcgorg:ICSC Approved A unified area command is established when incidents under an area command are multijurisdictional.
unified command National Incident Management System Integration Committee NIMSIC Approved Established when more than one agency has incident jurisdiction or when incidents cross political jurisdictions. This is accomplished by establishing a common set of incident objectives and strategies, without losing or abdicating authority, responsibility, or accountability.
Unified Ordering Point (UOP) Incident Business Committee IBC Approved Single location through which all incident resource orders are processed.
unique fire identifier National Coordination System Committee NCSC Approved A unique identifier assigned to each wildland fire.
unique fire report identifier FRSC Fire Reporting Subcommittee Approved A code that uniquely identifies a particular fire report.
unit (generic) National Incident Management System Integration Committee NIMSIC Approved A generic term that represents an organizational entity that only has meaning when it is contextualized by a descriptor, e.g. jurisdictional.
Unit Identifier (UnitID) UIB Unit Identifier Board Approved A code used within the interagency incident management community to uniquely identify a particular governmental or non-government organizational unit recognized by NWCG as a wildland fire or all-risk cooperator.
unity of command National Incident Management System Integration Committee NIMSIC Approved A NIMS guiding principle stating that each individual involved in incident management reports to and takes direction from only one person.
unity of effort Leadership Committee LC Approved A command philosophy that encourages leaders to work together to find common ground and act in the best interest of those responding to the incident, the public, and the resources that are threatened.
Universal Transverse Mercator easting coordinates Approved Grid coordinates expressed as a distance in meters to the east.
Universal Transverse Mercator northing coordinates Approved Coordinates measured relative to the equator.
Universal Transverse Mercator Zone Approved A division of the Earth's surface into 60 north-south zones, each 6 degrees of longitude wide.
unknown (remarks required) Communication, Education, and Prevention Committee CEPC In Development Used when the actual value is unavailable, uncertain or yet to be determined. It indicates that the information is missing or not applicable rather than representing an error or invalid entry.
unlined fire hose Equipment Technology Committee ETC Approved Hose commonly of cotton, linen, or synthetic fiber construction without rubber tube or lining, often used for wildfires because of its light weight and self protecting (weeping) characteristics; such hose is attached to first-aid standpipes in buildings. At a specified flow, friction loss in unlined hose of a stated diameter is about twice that of lined fire hose. 
unprotected lands IFPC Interagency Fire Planning Committee Approved Areas for which no fire organization has responsibility for management of a wildfire authorized by law, contract, or personal interest of the fire organization (e.g., a timber or rangeland association). 
unspecified shooting Communication, Education, and Prevention Committee CEPC In Development
upper level (cold) low Fire Weather Subcommittee FWS Approved Upper Level Disturbance, Cold Low Aloft: A circulation feature of the upper atmosphere where pressure, at a constant altitude, is lowest. Winds blow counter-clockwise around the center in an approximately circular pattern. Upper level lows are usually quite small. The mechanics of these upper lows is such that a pool of cool moist air always accompanies their development. There is often no evidence of low pressure at the earth's surface. An upper low may exist above a surface high pressure system. 
upper level (cold) trough Fire Weather Subcommittee FWS Approved Trough, Trough Aloft, Upper Level [Cold] Low: An elongated area of relatively low pressure, at constant altitude, in the atmosphere. The opposite of an upper level ridge. Upper level troughs are usually oriented north-south with the north end open. That is, air currents moving from west to east around the earth flow around three sides of the trough then turn eastward rather than toward the west, as in the case of a closed circulation. A large upper level trough may have one or more small upper level closed low circulation systems within it. 
upper level high Fire Weather Subcommittee FWS Approved Upper High, High Aloft, Upper Level Ridge: A circulation feature of the upper atmosphere where pressure, at a constant altitude, is higher than in the surrounding region. Winds blow clockwise around an upper level high. Air in an upper level high is usually subsiding. This results in comparatively warm dry air with light winds over a large area. An upper level high may exist without there being high pressure at the earth's surface. 
upper level ridge Fire Weather Subcommittee FWS Approved An elongated area of relatively high pressure, at a constant altitude, in the atmosphere. The opposite of an upper level trough. Upper level ridges are often oriented north-south, alternating between upper level troughs, however, during summer they may assume random orientations and vast dimensions. 
urban search/rescue/recovery (event) National Coordination System Committee NCSC Approved An event dealing with a search, and/or rescue, and/or recovery in an urban setting.
use level Equipment Technology Committee ETC Approved The appropriate ratio of liquid foam concentrate to water recommended by the chemical manufacturer for each class of fire, usually expressed as a percent (such as 0.5%).
use of wildland fire FMB Fire Management Board Approved Management of wildfire or prescribed fire to meet resource objectives specified in land/resource management plans.
useful load National Interagency Aviation Committee NIAC Approved Maximum computed gross weight minus equipped weight of a helicopter.
v pattern Communication, Education, and Prevention Committee CEPC Approved Characteristics fire cone-shaped pattern left by a fire on a wall, at or near its point of origin.
valley (topographic) External Source Approved A stretch of low land lying between hills or mountains which are sometimes occupied by a stream.
values at risk Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved The elements of a community or natural area considered valuable by an individual or community that could be negatively impacted by a wildfire or wildfire operations. These values can vary by community and can include diverse characteristics such as homes, specific structures, water supply, power grids, natural and cultural resources, community infrastructure, and other economic, environmental, and social values.
values to be protected Fire Use Subcommittee FUSC, IFPC Interagency Fire Planning Committee Approved Include property, structures, physical improvements, natural and cultural resources, community infrastructure, and economic, environmental, and social values.
vapor suppression Equipment Technology Committee ETC Approved Creating a seal with foam which prevents a release of flammable vapors from fuels.
variable Fire Weather Subcommittee FWS Approved Any changing characteristic; in statistics, a measurable characteristic of an experimental unit.
variable ceiling Fire Weather Subcommittee FWS Approved A ceiling of less than 3,000 feet (900 m) which rapidly increases or decreases in height by one or more reportable values during the period of observation.
variable danger FDSC Fire Danger Subcommittee Approved Resultant of all fire danger factors that vary from day to day, month to month, or year to year (e.g., fire weather, fuel moisture content, condition of vegetation, variable risk).
variable sky condition Fire Weather Subcommittee FWS Approved A sky condition that varies between reportable values of sky cover amounts during the period of observation.
variable visibility Fire Weather Subcommittee FWS Approved A condition when the prevailing visibility is less than 3 miles (5 km) and rapidly increases and decreases by one or more reportable values during the period of observation.
variable wind direction Fire Weather Subcommittee FWS Approved Wind direction which varies by 60 degrees or more during the period of time the wind direction is being determined.
vectors Fire Environment Committee FENC Approved Directions of fire spread as related to rate of spread calculations (in degrees from upslope).
vegetative regeneration Fire Use Subcommittee FUSC Approved Development of new aboveground plants from surviving plant parts, such as by sprouting from a root crown or rhizomes. Even if plants form their own root system, they are still genetically the same as the parent plant.
vegetative reproduction Fire Use Subcommittee FUSC Approved Establishment of a new plant from a seed that is a genetically distinct individual.
vehicle fire Wildland Fire Investigation Subcommittee WFISC Approved Fire originating in or on a vehicle or mobile equipment.
vehicle fire (event) National Coordination System Committee NCSC Approved An event dealing with a fire originating in or on a vehicle or mobile equipment.
Vehicle Identification Number (VIN) National Coordination System Committee NCSC Approved The Vehicle Identification Number (VIN) assigned to a piece of equipment.
vent Wildland Fire Investigation Subcommittee WFISC Approved The release of enclosed smoke and heat from a structure by creating openings in it, as by hacking a hole in the roof, to allow free passage of air.
ventilation factor Fire Weather Subcommittee FWS Approved A numerical value relating the potential of the atmosphere to disperse airborne pollutants from a stationary source, calculated by multiplying the mixing height by the transport wind speed.
ventilation index Fire Weather Subcommittee FWS Approved A measure of the volume rate of horizontal transport of air within the mixing layer, per unit distance, normal to the wind. Units are measured in square meters per second or knot-feet.
vertical fuel arrangement Fire Use Subcommittee FUSC Approved Fuels above ground and their vertical continuity, which influences fire reaching various levels or vegetation strata.
vertical temperature profile Fire Weather Subcommittee FWS Approved Plot of the actual dry-bulb temperature against height above the earth's surface, most commonly determined by a RAWINSONDE observation.
Very High Frequency (VHF-AM) National Coordination System Committee NCSC Approved Radio frequency range from 30 MHz to 299 MHz. The sub-bands most commonly used by fire are: VHF-FM Lo band: Frequency Modulation 30 MHz - 80 MHz, of which fire frequencies are between 30 MHz and 50 MHz. VHF-FM Hi band: Frequency Modulation 150 MHz - 174 MHz. This is the most widely used band by fire agencies. VHF-AM: Amplitude Modulation. This band is commonly referred to as the "Victor or VHF" band. The frequency range is from 118 MHz to 136 MHz. The only authorized use of this band is for aviation. The FAA controls and assigns all frequencies within this sub-band. 
VHF Omnidirectional Radio Range (VOR) National Coordination System Committee NCSC Approved System of radio navigation in which any magnetic bearing relative to a special radio transmitter on the ground may be chosen and flown by an aircraft pilot.
vigor Fire Use Subcommittee FUSC Approved A subjective assessment of the health of individual plants in similar site and growing conditions; or a more specific measure based upon a specific facet of growth, such as seed stalk or tiller production per plant or per unit area.
virga Fire Weather Subcommittee FWS Approved Precipitation falling out of a cloud but evaporating before reaching the ground.
viscosity Equipment Technology Committee ETC Approved Thickness of a liquid, the degree to which it resists flow.
viscous water Equipment Technology Committee ETC Approved Water that contains a thickening agent to reduce surface runoff; tends to cling to burning fuels and spread in layers that are several times thicker than plain water, thereby having an increased capacity to absorb heat, cool fuel, and exclude oxygen.
visibility Fire Weather Subcommittee FWS, Fire Use Subcommittee FUSC Approved The greatest horizontal distance at which selected objects can be seen and identified, or its equivalent derived from instrumental measurements.
visible area map IOSC Incident Operations Subcommittee Approved Map showing the different classes of visible area covered by a lookout point or points; may differentiate between seen areas, indirectly visible areas, and blind areas, or only between seen areas and blind areas. Also known as seen area map.
Visual Flight Rules (VFR) conditions National Interagency Aviation Committee NIAC Approved Basic weather conditions prescribed for flight under Visual Flight Rules: ceiling above 1,000 feet (300 m) and flight visibility in excess of 3 miles (5 km).
Visual Greenness (VG) FDSC Fire Danger Subcommittee Approved An NDVI-derived image of vegetation greenness compared to a very green reference such as a golf course.
visual range Fire Use Subcommittee FUSC Approved Maximum distance at which a given object can just be seen by an observer with normal vision.
Visual Resource Management (VRM) Fire Use Subcommittee FUSC Approved The inventory and planning actions taken to identify visual values and to establish objectives for managing those values; and the management actions taken to achieve the visual management objectives.
visual resources Fire Use Subcommittee FUSC Approved The visible physical features on a landscape (e.g., land, water, vegetation, animals, structures and other features).
visual search Wildland Fire Investigation Subcommittee WFISC Approved A systematic and thorough scan of the wildland fire environment for an object or feature as it relates to seeing or sight.  This scan may be aided by magnification when necessary.
volatile Communication, Education, and Prevention Committee CEPC Approved Readily changeable into vapor at low temperatures.
volatiles Fire Weather Subcommittee FWS Approved Readily vaporized organic materials which, when mixed with oxygen, are easily ignited.
volcano Communication, Education, and Prevention Committee CEPC In Development
volcano (event) National Coordination System Committee NCSC Approved An event dealing with response to volcanic activity.
volunteer IOSC Incident Operations Subcommittee Approved An appointment/agreement that meets the following conditions: The person does not receive compensation (other than reasonable reimbursement or allowance for expenses actually incurred)
volunteer fire company IOSC Incident Operations Subcommittee Approved A fire department company or a response unit, the members of which are not paid.
Volunteer Fire Department (VFD) IOSC Incident Operations Subcommittee Approved A fire department of which some or all members are unpaid.
volunteer firefighter IOSC Incident Operations Subcommittee Approved Legally enrolled firefighter under the fire department organization laws who devotes time and energy to community fire service without compensation other than Worker's Compensation or other similar death and injury benefits.
vortex turbulence National Interagency Aviation Committee NIAC Approved Miniature whirlwinds trailing from the wingtips of any aircraft in flight. Vortex will be in the form of a horizontal whirlwind with velocities up to 25 mph (40 km) per hour or more. Also created by action of rotor blades on helicopters; these whirlwinds tend to move downward toward the ground. If an aircraft flies low over a fire, vortices may reach the ground and suddenly cause violent and erratic fire behavior.
walk test Risk Management Committee RMC Approved The walk test is designed to determine the ability to carry out light duties. It consists of a one-mile test with no load that approximates an aerobic fitness score of 35. A time of 16 minutes, the passing score for this test, ensures the ability to meet emergency and evacuate to a safety zone. 
warm front Fire Weather Subcommittee FWS Approved The leading edge of a relatively warm air mass which moves in such a way that warm air replaces colder air that moves away from a region. Winds associated with warm frontal activity are usually light and mixing is limited. The atmosphere is relatively stable when compared to cold front activity.
warrant Incident Business Committee IBC Approved The official delegation of authority to contracting officers and procurement officers establishing the dollar amount and type limits for acquisitions.
water bar IOSC Incident Operations Subcommittee Approved A shallow channel or raised barrier, e.g., a ridge of packed earth or a thin pole laid diagonally across the surface of a road or trail so as to lead off water, particularly storm water. (Frequently installed in firelines on steep slopes to prevent erosion.) 
Water Expansion Pumping System (WEPS) Equipment Technology Committee ETC Approved Apparatus utilizing an air compressor and positive displacement pump coupled to the same engine, plumbed to a non-pressurized tank, for producing foam. The operation involves injecting compressed air into a liquid stream containing a suitable foaming agent.
Water Expansion System (WES) Equipment Technology Committee ETC Approved Apparatus utilizing a pressurized tank, hose, and nozzle for producing foam by injection of compressed air or gas into a liquid stream downstream from the pumping source. The liquid stream must contain a suitable foaming agent.
water hammer Equipment Technology Committee ETC Approved A force created by the rapid acceleration or deceleration of water, commonly created by opening or closing a valve too quickly. Pressures developed in a water hammer, proportional to the mass multiplied by the square of the velocity, can damage a pipe or hose. 
water source IOSC Incident Operations Subcommittee Approved Any strategically located supply of water that is readily available for pumps, tanks, trucks, helicopters, or fire camp use.
water source type IOSC Incident Operations Subcommittee Approved The type of water source.
water supply map Geospatial Subcommittee GSC Approved A map showing location of supplies of water readily available for pumps, tanks, trucks, camp use, etc.
water tender Equipment Technology Committee ETC Approved Any ground vehicle capable of transporting specified quantities of water.
water thief Equipment Technology Committee ETC Approved A type of bleeder valve designed for installation at convenient points in hose lines to permit drawing off water for filling backpack pumps or other use without interfering with pump or nozzle operation.
watercraft Communication, Education, and Prevention Committee CEPC In Development
waterway IFPC Interagency Fire Planning Committee In Development Any body of water including lakes, rivers, streams and ponds whether or not they contain aquatic life.
wave Fire Weather Subcommittee FWS Approved A disturbance that transfers energy from one point to another point and may take the form of a deformation of pressure or temperature. In the atmosphere such disturbances may result in major storms or merely result in changes in cloud, wind and temperature conditions. Development of a wave on a front usually slows the advance of the front due to transfer of energy to the wave development and movement. 
weather advisory Fire Weather Subcommittee FWS Approved In aviation forecasting, an expression of hazardous weather conditions not predicted in the zone weather forecast, as they affect the operation of air traffic.
weather concerns Fire Environment Committee FENC Approved A field collected in the ICS 209 containing a brief summary of how the current weather is affecting the incident and how the anticipated weather will affect the incident.
weighted monthly occurrence FDSC Fire Danger Subcommittee Approved Part of the National Fire Danger Rating System (NFDRS).  Number used to determine seasonal risk class for a protection unit, calculated by multiplying peak monthly average by two and adding seasonal monthly average.
wet Incident Business Committee IBC Approved The contractor furnishes all equipment operating supplies.
wet foam Equipment Technology Committee ETC Approved A low expansion foam type with few and varied bubbles and rapid drain time which is used for rapid penetration and fire extinguishment.
wet line IOSC Incident Operations Subcommittee Approved A line of water, or water and chemical retardant, sprayed along the ground, and which serves as a temporary control line from which to ignite or stop a low-intensity fire.
wet storage Equipment Technology Committee ETC Approved Fire retardants mixed with water and stored in tanks at air attack bases for immediate use by airtankers.
wet water Equipment Technology Committee ETC Approved Water with added chemicals, called wetting agents, that increase water's spreading and penetrating properties due to a reduction in surface tension.
wet-bulb depression Fire Weather Subcommittee FWS Approved The difference between the wet and dry-bulb temperatures recorded by a psychrometer; used in conjunction with the dry-bulb temperature as a measure of the relative humidity of the air.
wet-bulb temperature Fire Weather Subcommittee FWS Approved The lowest temperature to which air can be cooled by evaporating water into it at a constant pressure when the heat required for evaporation is supplied by the cooling of the air. It is measured by the wet bulb thermometer, which usually employs wetted wicking on the bulb as a cooling (through evaporation) device.
wet-bulb thermometer Fire Weather Subcommittee FWS Approved In a psychrometer, the thermometer with its bulb covered with a jacket of clean muslin which is saturated with distilled water before an observation.
wetting agent Equipment Technology Committee ETC Approved A chemical that when added to water reduces the surface tension of the solution and causes it to spread and penetrate exposed objects more effectively than the untreated water.
wetting rain Fire Weather Subcommittee FWS Approved A widespread rain that over an extended period of time significantly reduces fire danger. One-tenth of an inch may be sufficient to reduce fire danger in grass fuel models. One half inch may be necessary for timber fuels under closed canopies.
wheelbase Equipment Technology Committee ETC Approved The distance from the centerline of the front axle to the centerline of the rear axle. For a tandem rear axle vehicle the center line is midpoint between the centers of the two rear axles.
widow-maker Hazard Tree and Felling Subcommittee HTTFS Approved A loose limb, top, or piece of bark lodged in a tree, which may fall on anyone working beneath it.
wildfire FMB Fire Management Board Approved A wildland fire originating from an unplanned ignition, such as lightning, volcanos, unauthorized and accidental human caused fires, and prescribed fires that are declared wildfires.
wildfire (event) National Coordination System Committee NCSC Approved An event dealing with a wildland fire originating from an unplanned ignition, such as lightning, volcanos, unauthorized and accidental human caused fires, and prescribed fires that are declared wildfires.
wildfire response strategies wfnwcgorg:ICSC Approved The range of options available for response to a wildfire.
wildfire suppression IOSC Incident Operations Subcommittee Approved An appropriate management response to wildfire or prescribed fire that results in curtailment of fire spread and eliminates all identified threats from the particular fire.
wildland IOSC Incident Operations Subcommittee, Fire Environment Committee FENC Approved An area in which development is essentially non-existent, except for roads, railroads, powerlines, and similar transportation facilities. Structures, if any, are widely scattered.
wildland fire FMB Fire Management Board Approved Any non-structure fire that occurs in vegetation or natural fuels. Includes wildfires and prescribed fires.
Wildland Fire Assessment System (WFAS) FDSC Fire Danger Subcommittee Approved An internet-based information system, providing national views of weather and fire potential, including national fire danger and weather maps and satellite-derived greenness maps.
wildland fire leadership principles Leadership Committee LC Approved Eleven principles describing tangible behaviors that reflect and demonstrate the wildland fire leadership values.
wildland fire leadership values Leadership Committee LC Approved Three guiding values that should be the basis for the decisions that leaders make.
wildland fire module Fire Use Subcommittee FUSC Approved A group of 7-10 highly skilled personnel specifically associated with the planning and implementation of planned and unplanned wildland fire and hazardous fuels treatments. May be classified as a Type 1 or Type 2 dependent on qualifications and experience.
wildland fire serious accident Risk Management Committee RMC Approved Any accident where one or more fatalities occur and/or three or more personnel are inpatient hospitalized as a direct result, or in support of wildland fire suppression or prescribed fire operations. Accident may result in substantial property or equipment damage of $250,000 or more. 
wildland role UIB Unit Identifier Board Approved The responsibility of an organization related to wildland fire.
wildland search/rescue/recovery (event) National Coordination System Committee NCSC Approved An event dealing with a search, and/or rescue, and/or recovery in a wildland setting.
Wildland Urban Interface (WUI) FMB Fire Management Board Approved The line, area, or zone where structures and other human development meet or intermingle with undeveloped wildland or vegetation fuels.​​
Wildland Urban Interface indicator FRSC Fire Reporting Subcommittee, WMSC WUI Mitigation Subcommittee Approved A flag that indicates if the presence of Wildland Urban Interface (WUI) increased the cost or management complexity of a wildfire.
wind Fire Weather Subcommittee FWS Approved The horizontal movement of air relative to the surface of the earth.
wind direction Fire Weather Subcommittee FWS Approved Compass direction from which wind is blowing.
wind profile Fire Weather Subcommittee FWS Approved A chart of wind speed in relation to height, most commonly determined by a pilot balloon observation.
wind shear Fire Weather Subcommittee FWS Approved A variation in wind speed and/or direction in a layer of the atmosphere or between layers. The variation may be in the horizontal or vertical dimensions and may result in significant turbulence depending upon the magnitude of the wind speed/direction differences. A strong wind shear may act like an inversion and inhibit plume rise. It may also fracture the smoke plume, not allowing smoke to rise much above terrain levels. A strong horizontal anticyclonic shear results in downward motion and may bring smoke aloft to the surface.
wind shift (aviation) Fire Weather Subcommittee FWS Approved For aviation purposes, a change in the average wind direction of 45 degrees or more which takes place in less than 15 minutes if the wind speed during this period is 6 knots (3 m/s) or greater.
wind shift (ground observation) Fire Weather Subcommittee FWS Approved For ground observation purposes, a change of at least 45 degrees in the direction of a significant wind, which occurs in a relatively short time frame.
wind speed (open ground) Fire Weather Subcommittee FWS Approved Wind, in miles per hour, measured at 20 feet above open, level ground or as adjusted to meet this standard to compensate for height of ground cover, uneven ground, and nearby obstructions.
wind speed (velocity) Fire Weather Subcommittee FWS Approved Wind, in miles per hour, measured at 20 feet above ground, or above the average height of vegetation, and averaged over at least a 10-minute period.
wind turbine/windmills utility systems Communication, Education, and Prevention Committee CEPC In Development Electrical generation system consisting of a turbine(s) and tower(s). These systems convert wind's kinetic energy into electricity.
wind vectors Fire Weather Subcommittee FWS Approved Wind directions used to calculate fire behavior.
wind vortex flame wrap Wildland Fire Investigation Subcommittee WFISC Approved A char pattern that is created by the passage of wind around the trunk of a tree or pole-like object that creates vortices on the lee side and an area of stability.  The area of stability allows the heat and char pattern to rise higher on the lee side of the object.  Generally, the stronger the wind, the higher the wind vortex flame wrap will be.  White this is not a fire pattern indicator, it is a general indication of the direction of the wind at the time the pattern was created.
wind-driven wildland fire Fire Behavior Subcommittee FBSC Approved A wildland fire that is controlled by a strong consistent wind.
windfall Hazard Tree and Felling Subcommittee HTTFS Approved Tree that has been uprooted or broken off by wind.
windrow burning Fire Use Subcommittee FUSC Approved Burning slash that has been piled into long continuous rows. Also includes wildfire in vegetation planted to protect improvements or agriculture.
winds aloft Fire Weather Subcommittee FWS Approved Generally, wind speeds and wind directions at various levels in the atmosphere above the domain of surface weather observations.
windspeed meter Fire Weather Subcommittee FWS Approved A handheld device which indicates wind speed, usually in miles per hour.
woody fuel moisture Fire Weather Subcommittee FWS Approved In NFDRS, a calculated value representing the approximate moisture content of the live woody vegetation in the rating area expressed as a percentage of the oven dry weight of the sample.
woody vegetation condition Fire Weather Subcommittee FWS Approved A code reflecting the moisture content of the foliage and small twigs [less than 1/4 inch (0.6 cm)] of living woody plants.
Work Capacity Test (WCT) Risk Management Committee RMC Approved The Work Capacity Test (WCT) is a test to ensure a person is physically capable of meeting the minimum fitness requirement associated with assigned wildfire or prescribed fire duties as described in the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.  Below are the three defined duty levels with examples of associated essential functions:   Arduous Arduous duty field work requires above-average endurance and superior conditioning.  Duties may include an occasional demand for extraordinarily strenuous activity in emergency situations under adverse environmental conditions over extended periods. The pace of work typically is set by the emergency condition.  Essential functions include, but are not limited to: running, walking or hiking, climbing, jumping, twisting, bending, lifting more than 50 pounds, and carrying 45 pounds or more for extended periods over difficult terrain.  Moderate Moderate duty field work requires the average endurance and conditioning of an individual who possesses complete control of all their physical faculties. Occasional demands may be required for moderately strenuous activities in emergencies over long periods. The pace of work is usually set by the current environmental conditions.  Essential functions include, but are not limited to: considerable walking over irregular ground, standing for long periods, lifting 25 to 50 pounds, climbing, bending, stooping, squatting, twisting, and reaching. Light Light duty mainly involves office-type work with occasional field activity characterized by light physical exertion requiring basic good health.  Individuals almost always can govern the extent and pace of their physical activity.  Essential functions include, but are not limited to: climbing stairs, standing, operating a vehicle, and long hours of work, as well as some bending, stooping, or light lifting. The WCT consists of three separate levels of tests which correspond with the three duty types.  The tests are defined as follows: Pack Test - This is a job-related test to determine an individual’s ability to perform the minimum standards of arduous duty.  It consists of completing a 3-mile walk over level terrain in 45 minutes or less while carrying a 45-pound pack.   Field Test – This is a job-related test to determine an individual’s ability to perform the minimum standards of moderate duty. It consists of completing a 2-mile walk over level terrain in 30 minutes or less while carrying a 25-pound pack. Walk Test – This is a job-related test to determine an individual’s ability to perform the minimum standards of light duty.  The test consists of completing a 1-mile walk over level terrain in 16 minutes or less with no load. For more information about the Work Capacity Test consult the Work Capacity Test Administrator’s Guide, PMS 307.
work capacity test levels Risk Management Committee RMC Approved The WCT consists of three separate levels of tests which correspond with the three duty types. The tests are defined as Pack Test, Field Test, Walk Test.
work rate Incident Business Committee IBC Approved A daily, hourly, or mileage rate shall apply when equipment is under hire as ordered by the government and on shift, including relocation of equipment under its own power.
work/rest ratio Risk Management Committee RMC Approved An expression of the amount of rest that is required for each hour an individual is in work status. Current NWCG guidelines require one hour of rest for every two hours in work status.
woven jacket fire hose Equipment Technology Committee ETC Approved Fire hose of conventional construction, woven on looms from fibers of cotton or synthetic fibers. Most fire department hose is double jacketed (i.e., it has an outer jacket protecting the inner one against wear and abrasion).
wye Equipment Technology Committee ETC Approved A hose connection with two outlets permitting two connections of the same coupling diameter to be taken from a single supply line.
yard debris Communication, Education, and Prevention Committee CEPC In Development Use of fire to dispose of organic yard waste i.e bursh, tree limbs, leaves, and weeds.
zone weather forecast Fire Weather Subcommittee FWS Approved A portion of the general fire weather forecast issued on a regular basis during the normal fire season specifically to fit the requirements of fire management needs; i.e., time, areas, and weather elements. These zones or areas are a combination of administrative and climatological areas, usually nearly the size of an individual forest or district. 
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NWCG Latest Announcements

2024 Paul Gleason Award Winners Announced

Date:  March 13, 2026
Questions? 
Please contact: Leadership Committee

The NWCG Leadership Committee is proud to announce the recipients of the 2024 Paul Gleason "Lead By Example" awards. Award categories include Initiative and Innovation, Mentoring and Teamwork, Motivation and Vision, as well as a Lifetime Achievement Award.

Congratulations to the awardees:

  • Justin Baxter, National Unmanned Aerial System (UAS) Operations Specialist, with the U.S. Forest Service — Initiative and Innovation
  • Kelly Woods, Director of the Wildland Firefighting Lessons Learned Center — Mentoring and Teamwork
  • Doug Booster, Instructor, ProHealth Net, Inc. — Motivation and Vision
  • Pam McDonald, Writer-Editor for the National Interagency Fire Center — Lifetime Achievement Award

References:

Paul Gleason Lead By Example Award

Wildland Fire Leadership Development Program (WFLDP)

Leadership Committee

NEW! S-231, Engine Boss Course Available Now

Date:  March 6, 2026
Questions? 
Please contact: Incident Operations Subcommittee

NWCG is pleased to announce the new S-231, Engine Boss (Single Resource) course is now available on the Wildland Fire Learning Portal (WFLP). Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Engine Boss, Single Resource (ENGB) incident qualifications. 

This is a performance-based instructor-led training (ILT) that focuses on the application of ENGB responsibilities during wildland fire operations, emphasizing readiness, information gathering, risk management, engine tactics, and Wildland Urban Interface (WUI) operations. Trainees apply these skills through scenario-based group work and an optional field day that reinforces hands-on engine operation tasks. 

References:

S-231, Engine Boss (Single Resource) (Instructor-led)

NWCG Engine Boss, Single Resource (ENGB) Position Page

Wildland Fire Learning Portal

NWCG Celebrates 50 Years!

Date:  March 6, 2026
Questions? 
Please contact: NWCG Executive Secretary

NWCG is proud to celebrate 50 years of service to the wildland fire community. Beginning in 1976 with an interagency agreement between the Department of Interior and Department of Agriculture, NWCG has grown to include additional member agencies and is recognized as the standard-setting leader in wildland fire operations.

To honor where we’ve been and highlight where we are going, the NWCG team has created a video showcasing our history and accomplishments. The video is now available on the NWCG website.

References:

NWCG 50 Year Anniversary Video

NEW! S-131, Firefighter Type 1 Course Available Now

Date:  March 6, 2026
Questions? 
Please contact: Incident Operations Subcommittee

NWCG is pleased to announce the new S-131, Firefighter Type 1 course is now available on the Wildland Fire Learning Portal (WFLP). Developed through the Incident Performance and Training Modernization (IPTM) effort, this course is a performance-based instructor-led training (ILT) that focuses on the application of situational awareness and decision making, building on the knowledge and concepts introduced in previous required courses. Using a threaded fictitious fire, each unit focuses on a performance-based activity in which students practice applying their decision-making and problem-solving skills.

The S-131, Firefighter Type 1 course is required for individuals seeking qualifications to be a Firefighter Type 1 (Squad Boss) (FFT1) or an Incident Commander Type 5 (ICT5).

References:

S-131, Firefighter Type 1 (Instructor-led)

NWCG Firefighter Type 1 (Squad Boss) Position Page

NWCG Incident Commander Type 5 Position Page

Wildland Fire Learning Portal